what is function in php

A function in PHP is a block of code that can be reused many times in a program. It takes input in the form of parameters, processes it, and then returns a value. PHP has over 1000 built-in functions that can be called directly from within a script to perform a specific task. In addition, it is possible to create your own custom functions in PHP. A user-defined function declaration starts with the word "function" followed by the function name and the code to be executed. A function name must start with a letter or an underscore, and function names are not case-sensitive. The advantages of using functions in PHP include code reusability, less code, and easier understanding of the applications flow.