What type does 5 belong to in JavaScript?

JavaScript is a dynamically weakly typed language, and the type of a variable is determined by its value. There are seven built-in data types in JavaScript:

1. Basic data types (Primitive types): including Undefined, Null, Boolean, Number and String. These primitive types are simple pieces of data, and their values ​​are immutable.
2. Object type: Object type refers to complex data structures, including Function, Array, RegExp, etc., which are all instances of the Object type. The value of an object type can be modified.

According to this definition, 5 is not an object type, but a numeric type among the basic data types, because 5 is not a complex data structure, it is just a simple numerical value.

Specifically, the Number type in JavaScript can represent all numbers, including positive numbers, negative numbers, and 0, and can use scientific notation to represent very large or very small numbers. The Number type also has some special values, such as NaN (representing Not a Number), Infinity (representing positive infinity) and -Infinity (representing negative infinity).

In addition, it should be noted that JavaScript's Number type has some precision issues, because it uses 64-bit floating point numbers and cannot accurately represent all numbers. For example, the result of 0.1 0.2 is not 0.3, but an approximate number close to 0.3.

In addition to the Number type, there are some other basic data types in JavaScript:

• Undefined type: represents an undefined value, that is, the variable has not been initialized or assigned a value.
• Null type: represents a null value, that is, the value of the variable is null.
• Boolean type: represents a Boolean value, that is, true or false.
• String type: represents a string, that is, a sequence of characters.

In short, 5 belongs to the Number type in JavaScript. In JavaScript, numerical operations are very common operations. For developers, they need to understand the basic characteristics and operations of number types in JavaScript. rules for correct development.

The above is the detailed content of What type does 5 belong to in JavaScript?. For more information, please follow other related articles on the PHP Chinese website!