JavaScript Functions And Its Types

JavaScript Function: A function is used to group a set of statements then we can call no.of times any where in the project files. Functions are mainly used for re-usability.

Functions Are Mainly Two Types:

1. Pre Defined/ Bulletin Functions 
2. User Defined/ Derived Functions

Pre Defined/ Bulletin Functions :  Those functions which are defined by the system. We can use directly with out calling function definition.

Types of Pre Defined Functions: 

• Number Function
• Math Functions
• String Functions
• Date and Time Functions
• Input and Output Functions
• Array Functions
• DOM Functions

 User Defined/ Derived Functions: Those functions which are defined by the User. We can use directly by calling function definition which is defined by user.

Types of User Defined Functions:

• Function with no arguments and no return type
• Function with arguments and no return type
• Function with both arguments and with return type