This is a PHP built-in defined function that will provide the length of a string.
The string provided in the variable above contains 36 characters
This is a user defined function that will give a greeting to the specified name
Hello Bill , how are you today?
Hello Samantha , how are you today?
Hello Lauren , how are you today?
Hello Austin , how are you today?
User defined functions consist of the user supplying a variable into the function. Users can create unique function names and require 1 or multiple variables.
Pre-defined functions are frequently used functions that don't require to be defined and can simply be used to quickly run frequently.