What symbol must a variable start with in php?

PHP variable names must start with the following symbols: 1. Dollar sign ($) 2. Underscore (_) 3. Backslash (); but cannot start with numbers, punctuation marks, or reserved words.

Symbols at the beginning of PHP variables

In PHP, variable names must start with the following symbols:

• Dollar sign ($): This is the most commonly used variable symbol in PHP. For example: $variable_name.

Other valid symbols:

• Underscore (_): can be used as the first character of a variable name , but not common. For example: _variable_name.
• Backslash (\): Can only be used in a namespace to reference variables with global scope. For example: \\global_variable.

Invalid symbols:

• Numbers: Variable names cannot begin with a number. For example: 1variable_name.
• Punctuation: Variable names cannot begin with punctuation. For example: .variable_name.
• Reserved words: Variable names cannot use PHP reserved words. For example: echo, return.

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