How can variable naming conventions impact PHP code readability and functionality, as seen in the forum thread?

Variable naming conventions impact PHP code readability and functionality by making it easier for developers to understand the purpose of each variable. Consistent and descriptive variable names can help reduce confusion and errors in the code. By following naming conventions such as using camelCase or snake_case and choosing meaningful names, developers can improve the overall quality of their code.

// Bad variable naming convention
$var = 10;
$my_variable = "Hello";

// Good variable naming convention
$myVar = 10;
$greetingMessage = "Hello";