Javascript fresher interview questions with answers

Here are some JavaScript fresher interview questions with answers:

1. What is JavaScript?

JavaScript is a high-level, interpreted programming language that is used to create interactive web pages. It is one of the three core technologies of the World Wide Web, along with HTML and CSS.

2. What are the benefits of using JavaScript?

There are many benefits to using JavaScript, including:

• It is easy to learn: JavaScript is a relatively easy language to learn, even for beginners.
• It is versatile: JavaScript can be used to create a wide variety of web applications, from simple forms to complex games.
• It is cross-platform: JavaScript code can be run on any web browser, regardless of the operating system.

3. What are the limitations of using JavaScript?

There are a few limitations to using JavaScript, including:

• It is not as fast as some other languages: JavaScript is not as fast as some other languages, such as C++ or Java.
• It is not as secure as some other languages: JavaScript code can be manipulated by users, which can make it vulnerable to security attacks.
• It is not as scalable as some other languages: JavaScript code can be difficult to scale to large applications.

4. What are the different types of JavaScript variables?

There are three types of JavaScript variables:

• Primitive variables: Primitive variables store a single value, such as a number, a string, or a boolean.
• Object variables: Object variables store a collection of properties, each of which can have a value.
• Function variables: Function variables store a reference to a function.

5. What are the different types of JavaScript operators?

There are many different types of JavaScript operators, including:

• Arithmetic operators: Arithmetic operators are used to perform mathematical operations on numbers.
• Comparison operators: Comparison operators are used to compare two values and return a boolean value.
• Logical operators: Logical operators are used to combine two boolean values and return a single boolean value.
• Assignment operators: Assignment operators are used to assign a value to a variable.
• Special operators: Special operators are used for specific purposes, such as creating objects or calling functions.

6. What are the different types of JavaScript statements?

There are many different types of JavaScript statements, including:

• Expression statements: Expression statements evaluate an expression and return a value.
• Block statements: Block statements group together a set of statements.
• Conditional statements: Conditional statements allow you to execute different code depending on the value of a condition.
• Loop statements: Loop statements allow you to execute a block of code repeatedly.
• Function statements: Function statements define a function.

7. What are the different types of JavaScript events?

There are many different types of JavaScript events, including:

• DOM events: DOM events are events that occur in the Document Object Model, such as a mouse click or a key press.
• User events: User events are events that are generated by the user, such as a mouse click or a key press.
• Timer events: Timer events are events that are generated by a timer, such as a timeout or an interval.
• Network events: Network events are events that are generated by network activity, such as a request being made to a server or a response being received from a server.

8. What are the different ways to create a JavaScript object?

There are two ways to create a JavaScript object:

• Using the new keyword: The new keyword creates a new object and assigns it to a variable.
• Using the object literal syntax: The object literal syntax creates an object without assigning it to a variable.

9. What are the different ways to access the properties of a JavaScript object?

There are two ways to access the properties of a JavaScript object:

• Using the dot notation: The dot notation is used to access properties that are directly defined on the object.
• Using the bracket notation: The bracket notation is used to access properties that are defined on an object's prototype.

10. What are the different ways to iterate over the properties of a JavaScript object?

There are two ways to iterate over the properties of a JavaScript object:

• Using a for loop: A for loop can be used to iterate over the properties of an object in the order that they are defined.
• Using a for-in loop: A for-in loop can be used to iterate over the properties of an object, including properties that are defined on the object's prototype.