AJAX stands for Asynchronous JavaScript and XML. It is not a programming language but a combination of technologies that allows web applications or websites to send and receive data asynchronously without reloading the web page. AJAX improves the user experience of a web page by enabling it to update dynamically according to users’ actions or data changes.
In this article, we have listed some of the top AJAX interview questions and answers curated by web development experts.
1. What is Ajax?
- Ajax stands for Asynchronous JavaScript And XML.
- Ajax is used to send and retrieve data without reloading the website
- Ajax is used to update a webpage without reloading the webpage
2. What are the Advantages of Ajax?
- Enhances performance
- Better form validation
- Enables asynchronous processing
- Reduced bandwidth usage
- AJAX is user-friendly
- Bandwidth utilization
- Improves response time
- More interactive
- Supported by multiple browsers
- Bolsters user experience
- Speeder retrieval of data
3. What are the disadvantages of Ajax?
- Security issues
- Dependent on Javascript
- Debugging is difficult
- Slow network connection
- The source code is human-readable
4. What are the real web applications of Ajax currently running in the market?
- Facebook
- Gmail
- Twitter
- Javapoint
- Youtube
5. Is Javascript Knowledge required to do Ajax?
Yes, Javascript knowledge is required to do Ajax.
6. What are the security issues with Ajax?
- Ajax source code is readable.
- Attackers can penetrate the system.
7. Where the Ajax cannot be used?
Ajax cannot be used if
- the user wants to connect to a secured connection
- the browser does not support Javascript
8. What are the Browsers supported by Ajax?
- Netscape version 7.1 and above.
- Mozilla Firefox 1.0 and above.
- Apple Safari 1.2 and above.
- Konqueror.
- Microsoft Internet Explorer 5 and above.
- Opera 7.6 and above.
9. What are the different types of ready states in Ajax?
There are 4 ready states in Ajax:
- Initialization
- Request
- Process
- Ready
10. Are AJAX and XMLHttpRequest and the same thing?
No, XMLHttpRequest or XHR is used to send HTTP or HTTPS requests to a web server and load the response from the server back into the script.
11. What are the different types of postbacks in AJAX?
There are two types of postbacks in AJAX:
- Synchronous postback
- asynchronous postback
12. What are the controls available in AJAX?
The various controls available in AJAX are:
- Timer
- ScriptManagerProxy
- ScriptManager
- Update Progress
- UpdatePanel
13. What are the Ajax Debugging Tools?
AJAX applications debugging tools include:
- Firebug for Mozilla Firefox
- JavaScript HTML debugger
- Fiddler for IE (Internet Explorer)
- Script Debugger
- My Eclipse AJAX tools
14. What are the ready states of a request in AJAX?
There are 5 ready states of a request in AJAX. They are,
- UNOPENED
- OPENED
- HEADERS_RECEIVED
- LOADING
- DONE
15. What all are the technologies used by Ajax?
- XMLHttpRequest
- JavaScript
- Document Object Model (DOM)
- Cascading Style Sheets (CSS)
- Extensible HTML (XHTML)