What are the basic data types in js

js basic data types include Number, String, Boolean, Null, Undefined, Object and Symbol. Detailed introduction: 1. Number, numeric data type, including integers and floating point numbers. In JavaScript, all numbers are floating point types and can also represent special numerical values; 2. String, text data type, used to represent text or Character sequence, which can be a single character or a set of characters; 3. Boolean, etc.

The operating system for this tutorial: Windows 10 system, DELL G3 computer.

The basic data types (also called primitive data types) in JavaScript include Number, String, Boolean, Null, Undefined, Object and Symbol. The following is a detailed explanation of these basic data types:

1. Number: Numeric data type, including integers and floating point numbers. For example, 42, 3.14159. In JavaScript, all numbers are floating point types and can also represent special values, such as Infinity, -Infinity and NaN.

2. String: Text data type, used to represent text or character sequences. It can be a single character, or a collection of characters. For example, "Hello, World!". Strings are immutable, once created, they cannot be changed.

3. Boolean: logical data type, containing two values: true and false. Boolean values ​​are often used for conditional testing and logical operations.

4. Null: Null value data type, representing a null value or "none" value. It is usually used to indicate that an object variable does not point to any object.

5. Undefined: Undefined data type, indicating an undefined value, that is, the variable has not been assigned a value.

6. Object: Object data type, representing a set of key-value pairs. Objects can contain other objects, forming complex data structures. In JavaScript, all data is ultimately an object, except for primitive simple data types (such as booleans, numbers, and strings).

7. Symbol: Symbol data type, representing a unique identifier, often used as the key to object attributes. The symbol is unique and will not conflict with any other value.

In addition to these basic data types, JavaScript also introduces a special type: void. The void type is mainly used to represent a no-op operation, such as when there is no return value in a function.

These basic data types are the foundation of the JavaScript language. They have different characteristics, such as immutability, mutability, etc., and support different operations and functions. Understanding the characteristics and usage of basic data types is crucial to learning JavaScript in depth.

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