JavaScript Interview Questions and Answers

JavaScript Interview Questions and answers for beginners and experts. List of frequently asked JavaScript Interview Questions with answers by Besant Technologies. We hope these JavaScript Interview Questions and answers are useful and will help you to get the best job in the networking industry. This JavaScript Interview Questions and answers are prepared by JavaScript Professionals based on MNC Companies’ expectations. Stay tuned we will update New JavaScript Interview questions with Answers Frequently.

Best JavaScript Interview Questions and answers

HBinfotech solutions supports the students by providing JavaScript Interview Questions and answers for the job placements and job purposes. JavaScript is the leading important course in the present situation because more job openings and the high salary pay for this JavaScript and more related jobs. These are top JavaScript Interview Questions and answers, prepared by our institute experienced trainers.

JavaScript Interview Questions and answers for the job placements

Here is the list of most frequently asked JavaScript Interview Questions and Answers in technical interviews. These questions and answers are suitable for both freshers and experienced professionals at any level. The questions are for intermediate to somewhat advanced JavaScript professionals, but even if you are just a beginner or fresher you should be able to understand the answers and explanations here we give.

Q1) What is JavaScript?

JavaScript is a client-side as well as a server-side scripting Programming language that can be inserted into HTML pages Code and is understood by web browsers. JavaScript is also an Object-based Programming language.

Q2) What are JavaScript Data Types?

• String
• Function
• Boolean
• Object
• Number
• Undefined

Q3) What is the differentiation between JavaScript and Java?

Main differences between Java and JavaScript: Java is an OOP programming language while JavaScript is an OOP scripting language. Java creates a programming language that run under a virtual machine or browser while JavaScript code is run on a browser only. Java code requires to be compiled while JavaScript code is all in the text.

Q4) What close() makes in Javascript?

This is called a JavaScript closure Current Window. It performs it possible for a function to have “private” variables. The counter is covered by the scope of the unknown function, and can only be modified using the add function. A closure is a function having a path to the parent scope, even after the parent function has finished.

Q5) List some features of JavaScript It is an object-based scripting language.

• Given to the user more control over the browser.
• It’s Handling dates and time.
• It Identifying the user’s browser and OS
• It is interpreter based scripting language
• It is one of the case sensitive
• It’s mostly of the javascript control statements syntax is the same as the syntax of control statements in C language

Q6) What are the disadvantages of using inner HTML in JavaScript?

• The method of using inner HTML is much delayed than the rest of the variables as its content is slowly built into many elects and needs time to get re-parsed.
• While managing the inner HTML, the content gets replaced in JavaScript.
• Adding to inner HTML can’t be used correctly.
• Using inner HTML can also reveal the text of the JavaScript. Since no validation is needed by it, any type of
• valid inner HTML can be used. Even broken HTML can also be done and this can cause queries.
• The old content also gets quickly replaced.

Q7) What are Cookies in Javascript?

A Cookie is a store the variable on a client’s/visitors machine. Managing Cookies, the servers can recognize the client and the client’s transactions.

Q8) What is try catch in JavaScript?

JavaScript Errors – Throw and Try to Catch.The catch comment show handle the error. The throw statement lets you perform custom errors. The final report lets you execute code, after try and catch, blind of the result.

Q9) What is the role of JavaScript in a web page?

JavaScript, an object scripting program language which is used in web pages on with markup language HTML. JavaScript is quite successful and adopted largely by every web browser for its plan which provides dynamic content to get done in a webpage.

Q10) What are the different types of errors in JavaScript?

Load time errors: Errors which come up when storing a web page like odd syntax errors are known as Load-time errors and it makes the errors dynamically.
Runtime errors: In this error come due to abuse of the command inside the HTML language.
Logical Errors: These are the errors that occur due to the poor logic performed on a function which is just a different operation.