VARIABLES AND DATA TYPE IN PHP
Variables in PHP
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variables are the memory location which is used to hold the values.
A Variable is simply a container i.e used to store both numeric
and non-numeric information.
Rules for Variable declaration
Variables in PHP starts with a dollar($) sign, followed by
the name of the variable.
The variable name must begin with a letter or the underscore
character.
A variable name can only contain alpha-numeric characters and
underscores (A-z, 0-9, and _ )
A variable name should not contain space