1. What is the output of the following code?

   console.log(typeof null);
   

- A) "object"
- B) "null"
- C) "undefined"
- D) "boolean"

Answer: A) "object"

2. Which of the following is not a JavaScript data type?
- A) String
- B) Number
- C) Boolean
- D) Float

Answer: D) Float

3. What will the following code output?

   console.log(0 == '0');
   console.log(0 === '0');
   

- A) true, true
- B) true, false
- C) false, true
- D) false, false

Answer: B) true, false

4. **What is the purpose of the let keyword in JavaScript?**
- A) To declare a block-scoped variable
- B) To declare a global variable
- C) To declare a constant
- D) To declare a function
Answer: A) To declare a block-scoped variablele**
What will the following code output?t?**

   console.log(1 + "2" + "2");
   

- A) "122"
- B) "32"
- C) "14"
- D) "5"
Answer: A) "122"2"**
Which method is used to add an element to the end of an array?y?**
- A) push()
- B) pop()
- C) shift()
- D) unshift()

**Answer: A) push()**

7. **What is the output of the following code?**

   console.log(typeof NaN);
   

- A) "number"
- B) "NaN"
- C) "undefined"
- D) "Answer: A) "number") "number"**

8. **What does the this keyword refer to in a JavaScript method?**
- A) The function itself
- B) The global object
- C) The object that the method belongs to
- D) The paAnswer: C) The object that the method belongs tohod bWhat will the following code output?g code output?**

   console.log([] + []);
   

- A) "undefined"
- B) "null"
- C) ""
Answer: C) ""*AnsweWhich of the following is not a valid way to create a JavaScript object?Script object?**
- A) let obj = {};
- B) let obj = new Object();
- C) let obj = Object.create(null);
- D) let obj = new Object(null);

**Answer: D) let obj = new Object(null);**

11. **What is the output of the following code?**

    console.log(1 == true);
    console.log(0 == false);
    

- A) true, true
- B) true, false
- C) false, true
Answer: A) true, true*Answer: A) true, true**

12. **What is the purpose of the bind() method in JavaScript?**
- A) To bind a function to an object
- B) To bind an event to a function
- C) To bind a variable to a function
- D) To bind a Answer: A) To bind a function to an objectnd a fWhat will the following code output?the following code output?**

    console.log(typeof undefined);
    

- A) "undefined"
- B) "null"
- C) "objeAnswer: A) "undefined" **AnWhich of the following is not a JavaScript framework or library?ript framework or library?**
- A) React
- B) Angular
- Answer: D) Djangoo

What is the output of the following code?put of the following code?**

    console.log(2 + "2" - 1);
    

- A) "21"
- B) "22"
Answer: C) 21 D) 3

**Answer: C) 21**

16. **What is the purpose of the map() method in JavaScript?**
- A) To create a new array by applying a function to each element of an existing array
- B) To filter elements of an array based on a condition
- C) To reduce an array to a single value
- D) To sorAnswer: A) To create a new array by applying a function to each element of an existing arrayh elemWhat will the following code output?ill the following code output?**

    console.log(typeof []);
    

- A) "array"
- B) "object"
- C) "Answer: B) "object"ll"

Which of the following is not a valid JavaScript loop?s not a valid JavaScript loop?**
- A) for
- B) while
- C) do...while
- D) foreach

**Answer: D) foreach**

19. What is the output of the following code?

    console.log(1 === true);
    

- A) true
- B) false
- C) undefined
- D) null

Answer: B) false

20. **What is the purpose of the Promise object in JavaScript?**
- A) To handle asynchronous operations
- B) To handle synchronous operations
- C) To handle event listeners
- D) To handle DOM manipulation

Answer: A) To handle asynchronous operationsns**

These questions cover a range of JavaScript topics, including data types, operators, methods, and more, which are commonly asked in interviews.

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