PHP Veriables

• Variable is place holder to store the values
• PHP variable must specify with $key word
• $variable=value
• A variable starts with the $ sign, followed by the name of the variable
• Variable name should not start with number
• A variable name must start with a letter or the underscore character
• A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
• Variable names are case-sensitive ($age and $AGE are two different variables)
• Normal variables will override each other but constant variable will never support variable overriding concept
• Scope of Variables

Local Variables: Function variables are called local variables it will available only within the function

Argument variables: These are also available within the function only

Global variables: The scope of the global variable is entire class webpage if you want to use global variable inside a function must declare variable with global key word