How can code readability and maintainability be improved by using descriptive variable names instead of generic ones like $a, $b, etc. in PHP?

Using descriptive variable names instead of generic ones like $a, $b, etc. in PHP can greatly improve code readability and maintainability. Descriptive variable names provide context and meaning to the data being stored, making it easier for other developers (or even yourself in the future) to understand the code. By using meaningful variable names, you can convey the purpose of the variable and its value without needing additional comments or explanations.

// Bad practice: using generic variable names
$a = 10;
$b = 20;
$result = $a + $b;
echo $result;

// Good practice: using descriptive variable names
$firstNumber = 10;
$secondNumber = 20;
$sum = $firstNumber + $secondNumber;
echo $sum;