✅ Web development Interview Questions with Answers Part-2
11. What is the CSS box model and how does it work?
Answer
Every HTML element is a box.
It has content, padding, border, and margin.
The final size of an element is the sum of all four.
In real projects, I use box-sizing: border-box to keep layouts predictable.
12. What is the difference between margin and padding?
Answer
Margin controls space outside an element.
Padding controls space inside an element.
Margins separate elements.
Padding increases clickable and visual area.
Margins can collapse. Padding never collapses.
13. Explain the different CSS position values and their use cases.
Answer
Static is the default.
Relative moves an element relative to itself and helps position children.
Absolute positions an element relative to the nearest positioned parent.
Fixed sticks to the viewport during scroll.
Sticky behaves like relative until a scroll threshold, then becomes fixed.
14. What is the difference between display none, inline, block, and inline-block?
Answer
Display none removes the element from layout.
Block takes full width and starts on a new line.
Inline stays in the same line but ignores width and height.
Inline-block stays inline and respects width and height.
Inline-block is common for buttons.
15. What is the difference between Flexbox and CSS Grid?
Answer
Flexbox handles layout in one direction, row or column.
Grid handles layout in both rows and columns.
I use Flexbox for components and alignment.
I use Grid for page-level layouts.
16. How do you center a div vertically and horizontally?
Answer
I use Flexbox.
Set the parent to display flex.
Use justify-content center and align-items center.
It is clean, readable, and reliable across browsers.
17. How does CSS specificity work?
Answer
Specificity decides which CSS rule applies.
Inline styles override IDs.
IDs override classes.
Classes override elements.
If specificity matches, the last rule wins.
I avoid IDs in CSS to keep specificity low.
18. What is z-index and how does stacking context work?
Answer
z-index controls which element appears on top.
It only works on positioned elements.
A stacking context limits child z-index values.
Many modal bugs happen because of unexpected stacking contexts.
19. What are media queries and how do you build responsive layouts?
Answer
Media queries apply styles based on screen size.
I follow a mobile-first approach.
I start with small screens and scale up using min-width queries.
This improves performance and maintainability.
20. What are CSS preprocessors and why are they used?
Answer
Preprocessors extend CSS with variables, nesting, and mixins.
Sass is the most common.
They reduce repetition and improve structure.
Today, I use them selectively since modern CSS supports many features natively.
Double Tap ♥️ For Part-3
11. What is the CSS box model and how does it work?
Answer
Every HTML element is a box.
It has content, padding, border, and margin.
The final size of an element is the sum of all four.
In real projects, I use box-sizing: border-box to keep layouts predictable.
12. What is the difference between margin and padding?
Answer
Margin controls space outside an element.
Padding controls space inside an element.
Margins separate elements.
Padding increases clickable and visual area.
Margins can collapse. Padding never collapses.
13. Explain the different CSS position values and their use cases.
Answer
Static is the default.
Relative moves an element relative to itself and helps position children.
Absolute positions an element relative to the nearest positioned parent.
Fixed sticks to the viewport during scroll.
Sticky behaves like relative until a scroll threshold, then becomes fixed.
14. What is the difference between display none, inline, block, and inline-block?
Answer
Display none removes the element from layout.
Block takes full width and starts on a new line.
Inline stays in the same line but ignores width and height.
Inline-block stays inline and respects width and height.
Inline-block is common for buttons.
15. What is the difference between Flexbox and CSS Grid?
Answer
Flexbox handles layout in one direction, row or column.
Grid handles layout in both rows and columns.
I use Flexbox for components and alignment.
I use Grid for page-level layouts.
16. How do you center a div vertically and horizontally?
Answer
I use Flexbox.
Set the parent to display flex.
Use justify-content center and align-items center.
It is clean, readable, and reliable across browsers.
17. How does CSS specificity work?
Answer
Specificity decides which CSS rule applies.
Inline styles override IDs.
IDs override classes.
Classes override elements.
If specificity matches, the last rule wins.
I avoid IDs in CSS to keep specificity low.
18. What is z-index and how does stacking context work?
Answer
z-index controls which element appears on top.
It only works on positioned elements.
A stacking context limits child z-index values.
Many modal bugs happen because of unexpected stacking contexts.
19. What are media queries and how do you build responsive layouts?
Answer
Media queries apply styles based on screen size.
I follow a mobile-first approach.
I start with small screens and scale up using min-width queries.
This improves performance and maintainability.
20. What are CSS preprocessors and why are they used?
Answer
Preprocessors extend CSS with variables, nesting, and mixins.
Sass is the most common.
They reduce repetition and improve structure.
Today, I use them selectively since modern CSS supports many features natively.
Double Tap ♥️ For Part-3
❤13
𝗧𝗵𝗲 𝟯 𝗦𝗸𝗶𝗹𝗹𝘀 𝗧𝗵𝗮𝘁 𝗪𝗶𝗹𝗹 𝗠𝗮𝗸𝗲 𝗬𝗼𝘂 𝗨𝗻𝘀𝘁𝗼𝗽𝗽𝗮𝗯𝗹𝗲 𝗶𝗻 𝟮𝟬𝟮𝟲😍
Start learning for FREE and earn a certification that adds real value to your resume.
𝗖𝗹𝗼𝘂𝗱 𝗖𝗼𝗺𝗽𝘂𝘁𝗶𝗻𝗴:- https://pdlink.in/3LoutZd
𝗖𝘆𝗯𝗲𝗿 𝗦𝗲𝗰𝘂𝗿𝗶𝘁𝘆:- https://pdlink.in/3N9VOyW
𝗕𝗶𝗴 𝗗𝗮𝘁𝗮 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀:- https://pdlink.in/497MMLw
👉 Enroll today & future-proof your career!
Start learning for FREE and earn a certification that adds real value to your resume.
𝗖𝗹𝗼𝘂𝗱 𝗖𝗼𝗺𝗽𝘂𝘁𝗶𝗻𝗴:- https://pdlink.in/3LoutZd
𝗖𝘆𝗯𝗲𝗿 𝗦𝗲𝗰𝘂𝗿𝗶𝘁𝘆:- https://pdlink.in/3N9VOyW
𝗕𝗶𝗴 𝗗𝗮𝘁𝗮 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀:- https://pdlink.in/497MMLw
👉 Enroll today & future-proof your career!
❤1
✅ Web development Interview Questions with Answers Part-3
21. What is the difference between var, let, and const?
var is function scoped and allows redeclaration. let is block scoped and allows reassignment. const is block scoped and does not allow reassignment. I avoid var in modern code. I use const by default and let only when reassignment is required.
22. What is hoisting in JavaScript?
Hoisting is JavaScript’s behavior of moving declarations to the top of the scope. Function declarations are fully hoisted. Variables declared with var are hoisted but initialized as undefined. let and const are hoisted but not accessible before declaration. Accessing them early throws an error.
23. What is a closure and where do you use it?
A closure is a function that remembers variables from its outer scope, even after the outer function has finished execution. I use closures in callbacks, event handlers, and data privacy. They are common in React hooks and async code.
24. What is event bubbling and event capturing?
Event bubbling moves from the target element up to the parent. Event capturing moves from the parent down to the target. By default, JavaScript uses bubbling. I use event delegation based on bubbling for performance.
25. What is the difference between == and ===?
== compares values after type conversion. === compares both value and type. I always use === to avoid unexpected bugs.
26. What is the difference between arrow functions and regular functions?
Arrow functions do not have their own this. They inherit this from the parent scope. Regular functions have their own this based on how they are called. I use arrow functions for callbacks and functional code. I use regular functions for object methods when needed.
27. What are call, apply, and bind used for?
They control the value of this. call invokes a function with arguments passed individually. apply invokes a function with arguments as an array. bind returns a new function with this permanently set. bind is useful for event handlers and callbacks.
28. What are promises and how does async await work?
Promises handle asynchronous operations. They represent pending, fulfilled, or rejected states. async await is syntax sugar over promises. It makes async code readable and sequential. I use try catch for error handling with async await.
29. What is the difference between setTimeout and setInterval?
setTimeout runs code once after a delay. setInterval runs code repeatedly at fixed intervals. I clear both using clearTimeout and clearInterval. I avoid setInterval when accuracy matters.
30. What is the difference between debounce and throttle?
Debounce delays execution until the event stops firing. Throttle limits execution to a fixed interval. I use debounce for search input. I use throttle for scroll and resize events.
Double Tap ♥️ For Part-4
21. What is the difference between var, let, and const?
var is function scoped and allows redeclaration. let is block scoped and allows reassignment. const is block scoped and does not allow reassignment. I avoid var in modern code. I use const by default and let only when reassignment is required.
22. What is hoisting in JavaScript?
Hoisting is JavaScript’s behavior of moving declarations to the top of the scope. Function declarations are fully hoisted. Variables declared with var are hoisted but initialized as undefined. let and const are hoisted but not accessible before declaration. Accessing them early throws an error.
23. What is a closure and where do you use it?
A closure is a function that remembers variables from its outer scope, even after the outer function has finished execution. I use closures in callbacks, event handlers, and data privacy. They are common in React hooks and async code.
24. What is event bubbling and event capturing?
Event bubbling moves from the target element up to the parent. Event capturing moves from the parent down to the target. By default, JavaScript uses bubbling. I use event delegation based on bubbling for performance.
25. What is the difference between == and ===?
== compares values after type conversion. === compares both value and type. I always use === to avoid unexpected bugs.
26. What is the difference between arrow functions and regular functions?
Arrow functions do not have their own this. They inherit this from the parent scope. Regular functions have their own this based on how they are called. I use arrow functions for callbacks and functional code. I use regular functions for object methods when needed.
27. What are call, apply, and bind used for?
They control the value of this. call invokes a function with arguments passed individually. apply invokes a function with arguments as an array. bind returns a new function with this permanently set. bind is useful for event handlers and callbacks.
28. What are promises and how does async await work?
Promises handle asynchronous operations. They represent pending, fulfilled, or rejected states. async await is syntax sugar over promises. It makes async code readable and sequential. I use try catch for error handling with async await.
29. What is the difference between setTimeout and setInterval?
setTimeout runs code once after a delay. setInterval runs code repeatedly at fixed intervals. I clear both using clearTimeout and clearInterval. I avoid setInterval when accuracy matters.
30. What is the difference between debounce and throttle?
Debounce delays execution until the event stops firing. Throttle limits execution to a fixed interval. I use debounce for search input. I use throttle for scroll and resize events.
Double Tap ♥️ For Part-4
❤10👍1
𝗙𝘂𝗹𝗹𝘀𝘁𝗮𝗰𝗸 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 𝗵𝗶𝗴𝗵-𝗱𝗲𝗺𝗮𝗻𝗱 𝘀𝗸𝗶𝗹𝗹 𝗜𝗻 𝟮𝟬𝟮𝟲😍
Join FREE Masterclass In Hyderabad/Pune/Noida Cities
𝗛𝗶𝗴𝗵𝗹𝗶𝗴𝗵𝘁𝗲𝘀:-
- 500+ Hiring Partners
- 60+ Hiring Drives
- 100% Placement Assistance
𝗕𝗼𝗼𝗸 𝗮 𝗙𝗥𝗘𝗘 𝗱𝗲𝗺𝗼👇:-
🔹 Hyderabad :- https://pdlink.in/4cJUWtx
🔹 Pune :- https://pdlink.in/3YA32zi
🔹 Noida :- https://linkpd.in/NoidaFSD
Hurry Up 🏃♂️! Limited seats are available
Join FREE Masterclass In Hyderabad/Pune/Noida Cities
𝗛𝗶𝗴𝗵𝗹𝗶𝗴𝗵𝘁𝗲𝘀:-
- 500+ Hiring Partners
- 60+ Hiring Drives
- 100% Placement Assistance
𝗕𝗼𝗼𝗸 𝗮 𝗙𝗥𝗘𝗘 𝗱𝗲𝗺𝗼👇:-
🔹 Hyderabad :- https://pdlink.in/4cJUWtx
🔹 Pune :- https://pdlink.in/3YA32zi
🔹 Noida :- https://linkpd.in/NoidaFSD
Hurry Up 🏃♂️! Limited seats are available
✅ Web development Interview Questions with Answers Part-4
31. What is prototypal inheritance in JavaScript?
JavaScript uses prototype-based inheritance. Objects inherit properties from other objects through the prototype chain. When a property is not found, JavaScript looks up the chain. This avoids duplication and improves memory usage.
32. How does the this keyword behave in different contexts?
In the global scope, this refers to the window or undefined in strict mode. In a function, it depends on how the function is called. In a method, this refers to the object. In arrow functions, this is inherited from the parent scope.
33. What is the difference between shallow copy and deep copy?
Shallow copy duplicates references for nested objects. Deep copy duplicates everything. Shallow copy is faster but risky for nested data. I use structuredClone or JSON methods based on the use case.
34. How does the JavaScript event loop work?
JavaScript is single-threaded. The event loop handles asynchronous tasks. The call stack executes synchronous code first. Async tasks go to task queues. The event loop pushes tasks back to the stack when it is empty.
35. What is the difference between microtasks and macrotasks?
Microtasks have higher priority. Promises use the microtask queue. setTimeout uses the macrotask queue. Microtasks run before the next render cycle.
36. What causes memory leaks in JavaScript and how do you prevent them?
Uncleared timers. Detached DOM nodes. Unused global variables. I remove event listeners and clear intervals. I monitor memory using browser dev tools.
37. What are JavaScript modules and bundlers?
Modules allow code to be split into reusable files. Bundlers combine modules into optimized bundles. They handle dependency graphs and asset loading. Common tools include Webpack and Vite.
38. What is tree shaking and why is it important?
Tree shaking removes unused code from bundles. It reduces file size. It improves load time and performance. It works best with ES modules.
39. What are polyfills and when do you need them?
Polyfills add missing features to older browsers. They replicate modern APIs. I include them only when browser support requires it.
40. What are the different web storage options available in browsers?
Local storage persists data without expiration. Session storage clears on tab close. Cookies store small data and are sent with requests. I avoid storing sensitive data in all of them.
Double Tap ♥️ For Part-5
31. What is prototypal inheritance in JavaScript?
JavaScript uses prototype-based inheritance. Objects inherit properties from other objects through the prototype chain. When a property is not found, JavaScript looks up the chain. This avoids duplication and improves memory usage.
32. How does the this keyword behave in different contexts?
In the global scope, this refers to the window or undefined in strict mode. In a function, it depends on how the function is called. In a method, this refers to the object. In arrow functions, this is inherited from the parent scope.
33. What is the difference between shallow copy and deep copy?
Shallow copy duplicates references for nested objects. Deep copy duplicates everything. Shallow copy is faster but risky for nested data. I use structuredClone or JSON methods based on the use case.
34. How does the JavaScript event loop work?
JavaScript is single-threaded. The event loop handles asynchronous tasks. The call stack executes synchronous code first. Async tasks go to task queues. The event loop pushes tasks back to the stack when it is empty.
35. What is the difference between microtasks and macrotasks?
Microtasks have higher priority. Promises use the microtask queue. setTimeout uses the macrotask queue. Microtasks run before the next render cycle.
36. What causes memory leaks in JavaScript and how do you prevent them?
Uncleared timers. Detached DOM nodes. Unused global variables. I remove event listeners and clear intervals. I monitor memory using browser dev tools.
37. What are JavaScript modules and bundlers?
Modules allow code to be split into reusable files. Bundlers combine modules into optimized bundles. They handle dependency graphs and asset loading. Common tools include Webpack and Vite.
38. What is tree shaking and why is it important?
Tree shaking removes unused code from bundles. It reduces file size. It improves load time and performance. It works best with ES modules.
39. What are polyfills and when do you need them?
Polyfills add missing features to older browsers. They replicate modern APIs. I include them only when browser support requires it.
40. What are the different web storage options available in browsers?
Local storage persists data without expiration. Session storage clears on tab close. Cookies store small data and are sent with requests. I avoid storing sensitive data in all of them.
Double Tap ♥️ For Part-5
❤14👍1
✅ Web development Interview Questions with Answers Part-5
41. Why do we use frontend frameworks like React or Angular?
Answer: They help manage complex UI state. They enforce structure and reusability. They reduce manual DOM manipulation. This improves maintainability in large applications.
42. What is the Virtual DOM and how does it improve performance?
Answer: The Virtual DOM is a lightweight copy of the real DOM. Changes happen in memory first. Only the minimum required updates reach the real DOM. This reduces expensive DOM operations.
43. What are controlled and uncontrolled components?
Answer: Controlled components store input state in JavaScript. Uncontrolled components rely on the DOM for state. I prefer controlled components for validation and consistency. Uncontrolled components work for simple forms.
44. What is the difference between state and props?
Answer: Props pass data from parent to child. State manages local component data. Props are read-only. State changes trigger re-renders.
45. What are component lifecycle methods or hooks?
Answer: They let components react to creation, updates, and cleanup. In React, hooks replace lifecycle methods. useEffect handles side effects. Cleanup prevents memory leaks.
46. How does the dependency array in useEffect work?
Answer: It controls when the effect runs. Empty array runs once on mount. Values inside trigger re-runs on change. Wrong dependencies cause bugs or infinite loops.
47. When should you use Context API?
Answer: When data is needed across many components. Examples include theme, auth state, language. I avoid it for frequently changing data due to re-renders.
48. How do you optimize frontend application performance?
Answer: I avoid unnecessary re-renders. I memoize heavy components. I lazy-load routes. I reduce bundle size and API calls.
49. What is code splitting and why is it needed?
Answer: Code splitting loads only required code. It reduces initial bundle size. It improves first load performance. Commonly used with lazy loading.
50. What is the difference between server-side rendering and client-side rendering?
Answer: CSR renders content in the browser. SSR renders content on the server. SSR improves SEO and first paint. CSR works well for dashboards.
Double Tap ♥️ For Part-6
41. Why do we use frontend frameworks like React or Angular?
Answer: They help manage complex UI state. They enforce structure and reusability. They reduce manual DOM manipulation. This improves maintainability in large applications.
42. What is the Virtual DOM and how does it improve performance?
Answer: The Virtual DOM is a lightweight copy of the real DOM. Changes happen in memory first. Only the minimum required updates reach the real DOM. This reduces expensive DOM operations.
43. What are controlled and uncontrolled components?
Answer: Controlled components store input state in JavaScript. Uncontrolled components rely on the DOM for state. I prefer controlled components for validation and consistency. Uncontrolled components work for simple forms.
44. What is the difference between state and props?
Answer: Props pass data from parent to child. State manages local component data. Props are read-only. State changes trigger re-renders.
45. What are component lifecycle methods or hooks?
Answer: They let components react to creation, updates, and cleanup. In React, hooks replace lifecycle methods. useEffect handles side effects. Cleanup prevents memory leaks.
46. How does the dependency array in useEffect work?
Answer: It controls when the effect runs. Empty array runs once on mount. Values inside trigger re-runs on change. Wrong dependencies cause bugs or infinite loops.
47. When should you use Context API?
Answer: When data is needed across many components. Examples include theme, auth state, language. I avoid it for frequently changing data due to re-renders.
48. How do you optimize frontend application performance?
Answer: I avoid unnecessary re-renders. I memoize heavy components. I lazy-load routes. I reduce bundle size and API calls.
49. What is code splitting and why is it needed?
Answer: Code splitting loads only required code. It reduces initial bundle size. It improves first load performance. Commonly used with lazy loading.
50. What is the difference between server-side rendering and client-side rendering?
Answer: CSR renders content in the browser. SSR renders content on the server. SSR improves SEO and first paint. CSR works well for dashboards.
Double Tap ♥️ For Part-6
❤12👍1
💡 𝗠𝗮𝗰𝗵𝗶𝗻𝗲 𝗟𝗲𝗮𝗿𝗻𝗶𝗻𝗴 𝗶𝘀 𝗼𝗻𝗲 𝗼𝗳 𝘁𝗵𝗲 𝗺𝗼𝘀𝘁 𝗶𝗻-𝗱𝗲𝗺𝗮𝗻𝗱 𝘀𝗸𝗶𝗹𝗹𝘀 𝗶𝗻 𝟮𝟬𝟮𝟲!
Start learning ML for FREE and boost your resume with a certification 🏆
📊 Hands-on learning
🎓 Certificate included
🚀 Career-ready skills
🔗 𝗘𝗻𝗿𝗼𝗹𝗹 𝗙𝗼𝗿 𝗙𝗥𝗘𝗘 👇:-
https://pdlink.in/4bhetTu
👉 Don’t miss this opportunity
Start learning ML for FREE and boost your resume with a certification 🏆
📊 Hands-on learning
🎓 Certificate included
🚀 Career-ready skills
🔗 𝗘𝗻𝗿𝗼𝗹𝗹 𝗙𝗼𝗿 𝗙𝗥𝗘𝗘 👇:-
https://pdlink.in/4bhetTu
👉 Don’t miss this opportunity
👏2❤1
✅ Web development Interview Questions with Answers Part-6
51. What is REST architecture and its principles?
REST is an architectural style for APIs. It uses standard HTTP methods. It is stateless. Resources are identified by URLs. Responses are usually JSON. This keeps APIs simple and scalable.
52. What are HTTP methods and common HTTP status codes?
GET fetches data. POST creates data. PUT updates data. PATCH partially updates data. DELETE removes data. 200 means success. 201 means created. 400 means client error. 401 means unauthorized. 404 means not found. 500 means server error.
53. What does stateless architecture mean?
The server does not store client state. Each request contains all required information. This improves scalability and reliability. Authentication uses tokens instead of sessions.
54. What is the difference between authentication and authorization?
Authentication verifies identity. Authorization checks permissions. Login is authentication. Access control is authorization.
55. How does JWT-based authentication work?
User logs in with credentials. Server validates and generates a token. Token is sent with every request. Server verifies the token signature. No server-side session is stored.
56. What is the difference between cookies, local storage, and session storage?
Cookies are sent with every request. Local storage persists until cleared. Session storage clears when tab closes. I avoid storing sensitive data in all three.
57. What is CORS and how do you resolve CORS issues?
CORS restricts cross-origin requests. It is enforced by the browser. Server must allow required origins and headers. Misconfiguration causes blocked API calls.
58. What is middleware and why is it used?
Middleware runs between request and response. It handles logging, auth, validation. It keeps code modular and reusable.
59. Why is API versioning important?
It prevents breaking existing clients. It allows safe feature evolution. Versions are usually in URL or headers.
60. What is rate limiting and how is it implemented?
Rate limiting restricts request frequency. It protects APIs from abuse. It uses IP or user-based limits. Common tools include Redis-based counters.
Double Tap ♥️ For Part-7
51. What is REST architecture and its principles?
REST is an architectural style for APIs. It uses standard HTTP methods. It is stateless. Resources are identified by URLs. Responses are usually JSON. This keeps APIs simple and scalable.
52. What are HTTP methods and common HTTP status codes?
GET fetches data. POST creates data. PUT updates data. PATCH partially updates data. DELETE removes data. 200 means success. 201 means created. 400 means client error. 401 means unauthorized. 404 means not found. 500 means server error.
53. What does stateless architecture mean?
The server does not store client state. Each request contains all required information. This improves scalability and reliability. Authentication uses tokens instead of sessions.
54. What is the difference between authentication and authorization?
Authentication verifies identity. Authorization checks permissions. Login is authentication. Access control is authorization.
55. How does JWT-based authentication work?
User logs in with credentials. Server validates and generates a token. Token is sent with every request. Server verifies the token signature. No server-side session is stored.
56. What is the difference between cookies, local storage, and session storage?
Cookies are sent with every request. Local storage persists until cleared. Session storage clears when tab closes. I avoid storing sensitive data in all three.
57. What is CORS and how do you resolve CORS issues?
CORS restricts cross-origin requests. It is enforced by the browser. Server must allow required origins and headers. Misconfiguration causes blocked API calls.
58. What is middleware and why is it used?
Middleware runs between request and response. It handles logging, auth, validation. It keeps code modular and reusable.
59. Why is API versioning important?
It prevents breaking existing clients. It allows safe feature evolution. Versions are usually in URL or headers.
60. What is rate limiting and how is it implemented?
Rate limiting restricts request frequency. It protects APIs from abuse. It uses IP or user-based limits. Common tools include Redis-based counters.
Double Tap ♥️ For Part-7
❤13🙏1
✅ Web development Interview Questions with Answers Part-7
61. What is the difference between SQL and NoSQL databases?
SQL databases are relational and use structured schemas. They support joins and ACID transactions. NoSQL databases are schema-flexible and scale horizontally. I choose SQL for complex relationships. I choose NoSQL for high-scale or unstructured data.
62. What is database normalization?
Normalization organizes data to reduce duplication. It improves data integrity. It uses normal forms like 1NF, 2NF, and 3NF. I normalize by default and denormalize only for performance.
63. How does indexing improve database performance?
Indexes speed up read queries. They reduce full table scans. Indexes increase storage and slow writes. I index columns used in filters and joins.
64. What is the difference between primary key and foreign key?
Primary key uniquely identifies a row. Foreign key links one table to another. Primary keys enforce uniqueness. Foreign keys enforce referential integrity.
65. What are database transactions and ACID properties?
Transactions group operations into a single unit. Atomicity ensures all or nothing. Consistency keeps data valid. Isolation prevents conflicts. Durability ensures data persists after commit.
66. What are joins and when do you use them?
Joins combine data from multiple tables. INNER JOIN returns matching rows. LEFT JOIN returns all left rows. I use joins to avoid data duplication.
67. What are the advantages and disadvantages of using an ORM?
ORM speeds up development. It reduces boilerplate SQL. It can hide performance issues. I use ORM but write raw queries when needed.
68. What are common pagination strategies?
Offset-based pagination is simple but slow on large data. Cursor-based pagination is faster and scalable. I use cursor-based pagination for large datasets.
69. How do you validate data before storing it?
I validate at both client and server. I enforce schema-level validation. I sanitize inputs to prevent injection. Server-side validation is mandatory.
70. How do you prevent SQL injection attacks?
I use prepared statements. I avoid string concatenation. I validate and sanitize inputs. ORM query builders help reduce risk.
Double Tap ♥️ For Part-8
61. What is the difference between SQL and NoSQL databases?
SQL databases are relational and use structured schemas. They support joins and ACID transactions. NoSQL databases are schema-flexible and scale horizontally. I choose SQL for complex relationships. I choose NoSQL for high-scale or unstructured data.
62. What is database normalization?
Normalization organizes data to reduce duplication. It improves data integrity. It uses normal forms like 1NF, 2NF, and 3NF. I normalize by default and denormalize only for performance.
63. How does indexing improve database performance?
Indexes speed up read queries. They reduce full table scans. Indexes increase storage and slow writes. I index columns used in filters and joins.
64. What is the difference between primary key and foreign key?
Primary key uniquely identifies a row. Foreign key links one table to another. Primary keys enforce uniqueness. Foreign keys enforce referential integrity.
65. What are database transactions and ACID properties?
Transactions group operations into a single unit. Atomicity ensures all or nothing. Consistency keeps data valid. Isolation prevents conflicts. Durability ensures data persists after commit.
66. What are joins and when do you use them?
Joins combine data from multiple tables. INNER JOIN returns matching rows. LEFT JOIN returns all left rows. I use joins to avoid data duplication.
67. What are the advantages and disadvantages of using an ORM?
ORM speeds up development. It reduces boilerplate SQL. It can hide performance issues. I use ORM but write raw queries when needed.
68. What are common pagination strategies?
Offset-based pagination is simple but slow on large data. Cursor-based pagination is faster and scalable. I use cursor-based pagination for large datasets.
69. How do you validate data before storing it?
I validate at both client and server. I enforce schema-level validation. I sanitize inputs to prevent injection. Server-side validation is mandatory.
70. How do you prevent SQL injection attacks?
I use prepared statements. I avoid string concatenation. I validate and sanitize inputs. ORM query builders help reduce risk.
Double Tap ♥️ For Part-8
❤8🙏1
𝗙𝗥𝗘𝗘 𝗖𝗮𝗿𝗲𝗲𝗿 𝗖𝗮𝗿𝗻𝗶𝘃𝗮𝗹 𝗯𝘆 𝗛𝗖𝗟 𝗚𝗨𝗩𝗜😍
Prove your skills in an online hackathon, clear tech interviews, and get hired faster
Highlightes:-
- 21+ Hiring Companies & 100+ Open Positions to Grab
- Get hired for roles in AI, Full Stack, & more
Experience the biggest online job fair with Career Carnival by HCL GUVI
𝗥𝗲𝗴𝗶𝘀𝘁𝗲𝗿 𝗙𝗼𝗿 𝗙𝗥𝗘𝗘👇:-
https://pdlink.in/4bQP5Ee
Hurry Up🏃♂️.....Limited Slots Available
Prove your skills in an online hackathon, clear tech interviews, and get hired faster
Highlightes:-
- 21+ Hiring Companies & 100+ Open Positions to Grab
- Get hired for roles in AI, Full Stack, & more
Experience the biggest online job fair with Career Carnival by HCL GUVI
𝗥𝗲𝗴𝗶𝘀𝘁𝗲𝗿 𝗙𝗼𝗿 𝗙𝗥𝗘𝗘👇:-
https://pdlink.in/4bQP5Ee
Hurry Up🏃♂️.....Limited Slots Available
❤2
✅ Web development Interview Questions with Answers Part-8
71. What is MVC architecture?
MVC separates concerns into three parts:
• Model: Handles data and business logic
• View: Handles UI
• Controller: Handles user input and flow
This separation improves maintainability and testing.
72. What is the difference between monolithic and microservices architecture?
Monolithic architecture is a single deployable unit, simpler to start with, but scales as a whole. Microservices architecture splits functionality into independent services, more complex, but scales independently. Choice depends on team size and complexity.
73. What is an API gateway and why is it used?
An API gateway:
• Sits between clients and services
• Handles routing, auth, rate limiting
• Simplifies client communication
• Centralizes cross-cutting concerns
74. What caching strategies do you use in web applications?
• Client-side caching for static assets
• Server-side caching for frequent queries
• CDN caching for global delivery
Cache invalidation is handled carefully.
75. What is a CDN and how does it help performance?
A CDN:
• Serves content from locations closer to users
• Reduces latency
• Reduces server load
• Improves global performance
76. What is load balancing?
Load balancing:
• Distributes traffic across servers
• Improves availability and fault tolerance
Common methods include round robin and least connections.
77. What is the difference between scalability and performance?
• Performance: Speed for a single request
• Scalability: Handling increased load
A fast system that fails under load is not scalable.
78. What is the difference between horizontal and vertical scaling?
• Vertical scaling: Adds more resources to a server
• Horizontal scaling: Adds more servers
Horizontal scaling is more resilient.
79. What is the difference between WebSockets and HTTP?
• HTTP: Request-response based
• WebSockets: Persistent, two-way communication
Use WebSockets for real-time features like chat.
80. How do you handle file uploads securely?
• Validate file type and size
• Rename files to prevent collisions
• Store files outside the public directory
• Scan files when required
Double Tap ♥️ For Part-9
71. What is MVC architecture?
MVC separates concerns into three parts:
• Model: Handles data and business logic
• View: Handles UI
• Controller: Handles user input and flow
This separation improves maintainability and testing.
72. What is the difference between monolithic and microservices architecture?
Monolithic architecture is a single deployable unit, simpler to start with, but scales as a whole. Microservices architecture splits functionality into independent services, more complex, but scales independently. Choice depends on team size and complexity.
73. What is an API gateway and why is it used?
An API gateway:
• Sits between clients and services
• Handles routing, auth, rate limiting
• Simplifies client communication
• Centralizes cross-cutting concerns
74. What caching strategies do you use in web applications?
• Client-side caching for static assets
• Server-side caching for frequent queries
• CDN caching for global delivery
Cache invalidation is handled carefully.
75. What is a CDN and how does it help performance?
A CDN:
• Serves content from locations closer to users
• Reduces latency
• Reduces server load
• Improves global performance
76. What is load balancing?
Load balancing:
• Distributes traffic across servers
• Improves availability and fault tolerance
Common methods include round robin and least connections.
77. What is the difference between scalability and performance?
• Performance: Speed for a single request
• Scalability: Handling increased load
A fast system that fails under load is not scalable.
78. What is the difference between horizontal and vertical scaling?
• Vertical scaling: Adds more resources to a server
• Horizontal scaling: Adds more servers
Horizontal scaling is more resilient.
79. What is the difference between WebSockets and HTTP?
• HTTP: Request-response based
• WebSockets: Persistent, two-way communication
Use WebSockets for real-time features like chat.
80. How do you handle file uploads securely?
• Validate file type and size
• Rename files to prevent collisions
• Store files outside the public directory
• Scan files when required
Double Tap ♥️ For Part-9
❤7🥰2
𝗧𝗼𝗽 𝗖𝗲𝗿𝘁𝗶𝗳𝗶𝗰𝗮𝘁𝗶𝗼𝗻𝘀 𝗧𝗼 𝗚𝗲𝘁 𝗛𝗶𝗴𝗵 𝗣𝗮𝘆𝗶𝗻𝗴 𝗝𝗼𝗯 𝗜𝗻 𝟮𝟬𝟮𝟲😍
Opportunities With 500+ Hiring Partners
𝗙𝘂𝗹𝗹𝘀𝘁𝗮𝗰𝗸:- https://pdlink.in/4hO7rWY
𝗗𝗮𝘁𝗮 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀:- https://pdlink.in/4fdWxJB
📈 Start learning today, build job-ready skills, and get placed in leading tech companies.
Opportunities With 500+ Hiring Partners
𝗙𝘂𝗹𝗹𝘀𝘁𝗮𝗰𝗸:- https://pdlink.in/4hO7rWY
𝗗𝗮𝘁𝗮 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀:- https://pdlink.in/4fdWxJB
📈 Start learning today, build job-ready skills, and get placed in leading tech companies.
❤2
✅ Web development Interview Questions with Answers Part-9
81. What is XSS and how do you prevent it?
XSS happens when malicious noscripts run in the browser. It usually comes from unescaped user input. I prevent it by escaping output. I avoid innerHTML. I use content security policy.
82. What is CSRF and how do you protect against it?
CSRF forces users to perform unwanted actions. It exploits trusted sessions. I use CSRF tokens. I use same-site cookies. I verify request origin.
83. Why is HTTPS important and how does TLS work?
HTTPS encrypts data in transit. TLS handles encryption and key exchange. It prevents man-in-the-middle attacks. It ensures data integrity.
84. How should passwords be stored securely?
Passwords are never stored in plain text. I hash them using bcrypt or argon2. I use salt. I apply proper hashing cost.
85. Why should environment variables be used for secrets?
They keep secrets out of source code. They differ per environment. They reduce accidental exposure in repositories.
86. What are secure HTTP headers?
They protect against common attacks. Examples include CSP, HSTS, X-Frame-Options. I configure them at server or proxy level.
87. What are common OWASP security risks?
Injection attacks. XSS. Broken authentication. Sensitive data exposure. I follow OWASP guidelines during development.
88. What is role-based access control?
RBAC restricts access based on roles. Permissions are tied to roles, not users. It simplifies access management.
89. How do you sanitize user input?
I validate input type and length. I escape output. I use libraries instead of manual parsing.
90. How do you securely store uploaded files?
I validate file content. I change file names. I restrict execution. I store files outside public folders.
Double Tap ♥️ For Part-10
81. What is XSS and how do you prevent it?
XSS happens when malicious noscripts run in the browser. It usually comes from unescaped user input. I prevent it by escaping output. I avoid innerHTML. I use content security policy.
82. What is CSRF and how do you protect against it?
CSRF forces users to perform unwanted actions. It exploits trusted sessions. I use CSRF tokens. I use same-site cookies. I verify request origin.
83. Why is HTTPS important and how does TLS work?
HTTPS encrypts data in transit. TLS handles encryption and key exchange. It prevents man-in-the-middle attacks. It ensures data integrity.
84. How should passwords be stored securely?
Passwords are never stored in plain text. I hash them using bcrypt or argon2. I use salt. I apply proper hashing cost.
85. Why should environment variables be used for secrets?
They keep secrets out of source code. They differ per environment. They reduce accidental exposure in repositories.
86. What are secure HTTP headers?
They protect against common attacks. Examples include CSP, HSTS, X-Frame-Options. I configure them at server or proxy level.
87. What are common OWASP security risks?
Injection attacks. XSS. Broken authentication. Sensitive data exposure. I follow OWASP guidelines during development.
88. What is role-based access control?
RBAC restricts access based on roles. Permissions are tied to roles, not users. It simplifies access management.
89. How do you sanitize user input?
I validate input type and length. I escape output. I use libraries instead of manual parsing.
90. How do you securely store uploaded files?
I validate file content. I change file names. I restrict execution. I store files outside public folders.
Double Tap ♥️ For Part-10
❤4
✅ Web development Interview Questions with Answers Part-10
91. What is the difference between git merge and git rebase?
Merge keeps commit history intact and adds a merge commit. Rebase rewrites history into a linear flow. I use merge on shared branches. I use rebase on local feature branches before pushing.
92. What is a CI/CD pipeline?
It automates build, test, and deployment. CI validates every commit. CD deploys changes safely. This reduces human error and speeds delivery.
93. Why is Docker used in modern development?
Docker packages code with dependencies. It removes environment mismatch issues. It makes deployments predictable. I use it for local development and production parity.
94. What are environment-based builds?
They separate config per environment. Dev, staging, and production behave differently. Secrets and API URLs change per environment. This prevents accidental production issues.
95. How do you handle logging and monitoring?
I log meaningful events, not noise. I track errors, latency, and traffic. I use centralized logging and alerts. This helps detect issues early.
96. How do you design error handling in applications?
I handle errors gracefully. I return clear error responses. I log errors with context. I never expose internal stack traces to users.
97. What tools do you use to monitor performance?
I monitor response time and resource usage. I use APM tools and browser metrics. I track slow queries and API latency.
98. How do you debug issues in production?
I start with logs and metrics. I reproduce the issue in staging if possible. I add temporary logs if needed. I fix root cause, not symptoms.
99. How do you write clean and maintainable code?
I keep functions small. I use clear naming. I avoid duplication. I write tests for critical logic. I review code regularly.
100. How do you handle failures and outages in real-world systems?
I stay calm and assess impact. I roll back if needed. I communicate clearly with stakeholders. I write a postmortem. I fix the process, not blame people.
Double Tap ♥️ For More
91. What is the difference between git merge and git rebase?
Merge keeps commit history intact and adds a merge commit. Rebase rewrites history into a linear flow. I use merge on shared branches. I use rebase on local feature branches before pushing.
92. What is a CI/CD pipeline?
It automates build, test, and deployment. CI validates every commit. CD deploys changes safely. This reduces human error and speeds delivery.
93. Why is Docker used in modern development?
Docker packages code with dependencies. It removes environment mismatch issues. It makes deployments predictable. I use it for local development and production parity.
94. What are environment-based builds?
They separate config per environment. Dev, staging, and production behave differently. Secrets and API URLs change per environment. This prevents accidental production issues.
95. How do you handle logging and monitoring?
I log meaningful events, not noise. I track errors, latency, and traffic. I use centralized logging and alerts. This helps detect issues early.
96. How do you design error handling in applications?
I handle errors gracefully. I return clear error responses. I log errors with context. I never expose internal stack traces to users.
97. What tools do you use to monitor performance?
I monitor response time and resource usage. I use APM tools and browser metrics. I track slow queries and API latency.
98. How do you debug issues in production?
I start with logs and metrics. I reproduce the issue in staging if possible. I add temporary logs if needed. I fix root cause, not symptoms.
99. How do you write clean and maintainable code?
I keep functions small. I use clear naming. I avoid duplication. I write tests for critical logic. I review code regularly.
100. How do you handle failures and outages in real-world systems?
I stay calm and assess impact. I roll back if needed. I communicate clearly with stakeholders. I write a postmortem. I fix the process, not blame people.
Double Tap ♥️ For More
❤9👍1
𝗧𝗼𝗽 𝗖𝗲𝗿𝘁𝗶𝗳𝗶𝗰𝗮𝘁𝗶𝗼𝗻𝘀 𝗢𝗳𝗳𝗲𝗿𝗲𝗱 𝗕𝘆 𝗜𝗜𝗧 𝗥𝗼𝗼𝗿𝗸𝗲𝗲 & 𝗜𝗜𝗠 𝗠𝘂𝗺𝗯𝗮𝗶😍
Placement Assistance With 5000+ Companies
Deadline: 25th January 2026
𝗗𝗮𝘁𝗮 𝗦𝗰𝗶𝗲𝗻𝗰𝗲 & 𝗔𝗜 :- https://pdlink.in/49UZfkX
𝗦𝗼𝗳𝘁𝘄𝗮𝗿𝗲 𝗘𝗻𝗴𝗶𝗻𝗲𝗲𝗿𝗶𝗻𝗴:- https://pdlink.in/4pYWCEK
𝗗𝗶𝗴𝗶𝘁𝗮𝗹 𝗠𝗮𝗿𝗸𝗲𝘁𝗶𝗻𝗴 & 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀 :- https://pdlink.in/4tcUPia
Hurry..Up Only Limited Seats Available
Placement Assistance With 5000+ Companies
Deadline: 25th January 2026
𝗗𝗮𝘁𝗮 𝗦𝗰𝗶𝗲𝗻𝗰𝗲 & 𝗔𝗜 :- https://pdlink.in/49UZfkX
𝗦𝗼𝗳𝘁𝘄𝗮𝗿𝗲 𝗘𝗻𝗴𝗶𝗻𝗲𝗲𝗿𝗶𝗻𝗴:- https://pdlink.in/4pYWCEK
𝗗𝗶𝗴𝗶𝘁𝗮𝗹 𝗠𝗮𝗿𝗸𝗲𝘁𝗶𝗻𝗴 & 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀 :- https://pdlink.in/4tcUPia
Hurry..Up Only Limited Seats Available
❤1