What are some common mistakes to avoid when working with variable names in PHP code?

One common mistake to avoid when working with variable names in PHP code is using reserved keywords as variable names. This can lead to unexpected behavior and errors in your code. To solve this issue, always use unique and descriptive variable names that do not conflict with PHP's reserved keywords.

// Incorrect: Using a reserved keyword as a variable name
$echo = "Hello, World!";

// Correct: Using a unique and descriptive variable name
$message = "Hello, World!";