What symbol must a variable start with in php?

In PHP, variables start with a dollar sign ($) and the rules are as follows: Variable names must start with a dollar sign ($). Variable names can only contain letters, numbers, and underscores (_). Variable names cannot start with a number. Variable names are case-sensitive. Variable names cannot be the same as PHP keywords or reserved words.

Rules for PHP variable naming: start with a dollar sign

In PHP, variable names must start with a dollar sign ($) begins. This is a syntactic requirement to distinguish variables from other elements.

Rule Description:

• All variable names must begin with a dollar sign ($).
• Variable names can only contain letters, numbers, and underscore (_) characters.
• Variable names cannot start with a number as it may be confused with a numerical value.
• Variable names are case-sensitive. For example, $name and $Name are two different variables.
• Variable names cannot be the same as PHP keywords or reserved words.

Example:

Valid variable names:

• $name
• $user_age
• $_SERVER

Invalid variable name:

• 1age (starts with a number)
• name (does not start with a dollar sign)
• UserAge (case sensitive)
• var (is a PHP keyword)

Note:

• Although starting with a dollar sign is a requirement for variable names, it is recommended to use meaningful and descriptive variable names.
• Use an underscore ( _ ) to join multiple words together to improve readability, such as $user_name.
• Avoid using special characters or spaces as they may cause syntax errors.

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