Top 30+ Web Developer Interview Questions & Answers

Web Development is a booming sector, where there are many vacancies. For everyone out there whether you have been in the developer position for some time or a starter looking for your initial job, you need to prepare for your web developer interviews. This blog will explain more than 30 essential web developer interview questions and answers in plain English.

    1. What is Web Development?

Answer: Web development in simple terms entails website or web application construction. It ranges from generating small HTML pages without graphics to rich graphical dynamic Web sites. The three core elements of web development are the front-end, back-end, and full-stack.  

    2. What differentiates between HTML, CSS, and JavaScript?

Answer:

• The foundation of a webpage is HTML or Hypertext Markup Language. It sets out the things such as headings, paragraphs, links as well as images.
• The webpage is styled using CSS which stands for Cascading Style Sheets. It regulates the placement, color, type, and every other feature of the design.
• The interactive webpage is made out of JavaScript. It can change content, check if forms have been filled properly, and even design animated sections. 

    3. What is a Front-End Developer?

Answer: A Front-End Developer develops the area, which a user sees and can engage with when visiting the website. HTML, CSS, and JavaScript are employed to come up with designs that are responsive and generally unique in appearance.

    4. What is a Back-End Developer?

Answer: Back-End Developer is someone who deals with the back-end of applications that you constantly use. Change data capture tools deals with databases, servers, APIs as well as application logic. PHP, Python, Ruby, and Node.js are a few of the languages that are utilized. 

    5. What is Full-Stack Development?

Answer: Full-stack development simply means that a developer is capable of working on both, ends of the web application or the browser side and the server side. Full-stack developers apply HTML, CSS, JavaScript, and server-side languages when creating end solutions for Web applications.

    6. What is the DOM (Document Object Model)?

Answer: DOM stands for Document Object Model. It serves as a representation of an HTML document's layout. JavaScript can be used to alter or manipulate other contents of a web page. The DOM represents all of the elements of a page (headings, paragraphs, etc.) as objects that can be manipulated by scripts.

    7. What are Responsive web designs?

Answer: Responsive Web Design entails a method that makes a website visible and accessible across all devices (desktops, tablets, mobiles). It employs the use of relative and fluid designs, purses along with media queries to enhance the layout on the various screens.

    8. How are '==' and '===' used differently in JavaScript?

Answer:

• "==" only compares values; if the data types differ, it automatically converts them. 
• "===" Which compares both values and data types. It doesn't change the data types; hence it is stricter and more accurate.

    9. What is CSS Flexbox?

Answer: CSS Flexbox is a layout model that aims to help you build flexible layouts. That makes it possible to properly align objects on the page in case the size of these objects can vary in the process of the page’s construction.

   10. What is a CSS Grid?

Answer: The other layout system to assist in developing complex web designs is CSS Grid. Flexbox is a one-dimensional layout means, it has only a row or a column but CSS Grid is a two-dimensional layout means, it has a row as well as a column.

   11. What are the different data types in JavaScript?

Answer: JavaScript has several data types for use as follows:

• String: Digital text data such as Hello World.
• Number: Numeric data, e.g., 10, 3.14
• Boolean: This takes either true or false values
• Object: An evolution of key-value maps
• Array: it is comparable to a list of values. 
• Null: Represents no value
• Undefined: Stands for a variable that employs no value at that particular time.

   12. What is AJAX in web development?

Answer: AJAX (Asynchronous JavaScript and XML) is a technique that enables the loading of contents inside the Web page without changing the whole Web page. It helps to make websites more effective and gives improved user experience as it is answered from a server in the background.

   13. What is REST API?

Answer: REST API (Representational State Transfer Application Programming Interface) is a protocol that governs how the client and server transactions occur over the HTTP. It is used to ask for and dispatch data in formats such as JSON or XML.

   14. What is JSON?

Answer: JSON is a data form that has been designed for easy storage and usage through the use of a notation system. It is very simple to learn and use for the implicit purpose of passing data between a client and a server.

   15. What differentiates between GET and POST requests?

Answer:

• GET is employed when one wants to ask the server for some data. It appends data to the URL.
• POST is employed to pass data to the server especially when filling forms. It can contain data in the body of the request; this is safer than the GET method.

   16. What is Git?

Answer: Git is a distributed version control system that is used to maintain a list of changes and keep developers working on the same project synchronized with each other. GitHub is an online hosting for version control for software development using Git.

   17. What is a framework in web development?

Answer: A framework is a set of often complex established code pieces that assist developers when coding applications. It offers pre-built classes and a way to structure your code. These frameworks entail React, Angular, and Vue.js for front-end development and Express.js for back-end development.

   18. What is Node.js?

Answer: Node.js can be described as a new server-side JavaScript platform where JS is executed on a server-side. Node.com stems from Chrome, with plans to build it on the V8 JavaScript motor, and is utilized primarily for delineating high-performance and obtainable network applications.

   19. What is a Content Management System (CMS)?

Answer: It’s a system that assists you in content management and creation within your organization or company. Users can develop websites under this kind of service without any coding knowledge. These consist of Drupal, Joomla, and WordPress.   

   20. What is Bootstrap?

Answer: Bootstrap is a well-known front-end framework it involves a simply constructed plan that can be used to build a responsive website on short notice. It is made up of CSS and JS components, including forms, modals, and navigation. 

   21. What is a cookie in web development?

Answer: A cookie is a little file that is saved in a user's browser and frequently contains a small amount of data. It can be employed to retain login information, and preferences, or monitor the action of a user on a website.

   22. What role does the "div" tag play in HTML?

Answer: The div tag is always used to group other tags’ content to create complex layouts. It assists in the application of style and positioning objects or an item on the webpage.

   23. What is the contrast between synchronous and asynchronous programming?

Answer:

• Synchronous programming has the meaning where each of the processes is being performed one at a time.
• There is also the possibility of doing several things at once using asynchronous programming and never waiting for the previous activity to be completed.

   24. What are WebSockets?

Answer: WebSockets offer bidirectional real-time connection through one TCP connection only. This implies that it will enable continuous communication between a client and a server and therefore will suit applications like chat and notifications.

   25. What is the difference between sessionStorage and localStorage?

Answer:

• While using SessionStorage is permanent, it only remains for the entire current browser session and saves data for a particular page session. It only gets cleared when the browser is closed down, in the process of erasing all the items already stored within it.
• localStorage remains valid up to the time that data is removed and it doesn’t have a limit of expiring when the browser is closed.

   26. What is Cross-Origin Resource Sharing (CORS)?

Answer: CORS is a feature in the browser that controls whether web applications send requests to a different domain from the origin, protocol, domain, or port. It assists in limiting access to resources in a way that only the rightful users should access them.

   27. What is a database?

Answer: A database is a structured set of data that can be stored, retrieved manipulated efficiently, and changed as needed. In web development, we have various data storage mechanisms; some of them include; MySQL, MongoDB, and PostgreSQL.

   28. What differentiates SQL and NoSQL databases?

Answer:

• SQL databases store information in tables and manage information by using structured query language (e.g., MySQL, PostgreSQL).
• NoSQL databases are non-relational and store data in formats like JSON or key-value pairs, such as MongoDB and Firebase.

   29. What is the use of version control systems like Git?

Answer: Out of the versioning system, Git is used by the developer to track changes made to the code, roll back, and work on multiple copies in a single environment. And it just makes large projects much more manageable.

   30. What is the difference between JavaScript and TypeScript?

Answer: JavaScript delivers dynamic features for web development, and on the other side; TypeScript is a refined form of JavaScript with an additional feature called static typing. TypeScript is effective in capturing mistakes at the early stage and increases structure in the code implementation.

Conclusion

In conclusion, the above interview questions for web developers will enable you to ascertain the sort of questions that might be asked in the web development interviews. However, if you want to become an expert who can compete for the required technical round interviews in any given organization, you should take an online web development course. At BBSMIT, there are different online web development courses given for your reading to enhance your web development understanding as well as enhance your chances of passing an interview a boosting your career.