Variable Scope and Variable Naming In PHP

Variable Scope

Scope can be defined as the range of availability a variable has to the program in which it is declared. PHP variables can be one of four scope types:

• Local variables
• Function parameters
• Global variables
• Static variables

Variable Naming:

Rules for naming a variable is:

• Variable names must begin with a letter or underscore character.
• A variable name can consist of numbers, letters, underscores but you cannot use characters like + , - , % , ( , ) . & , etc
  There is no size limit for variables.