How can efficient variable naming conventions improve code readability in PHP?

Efficient variable naming conventions can improve code readability in PHP by making it easier for developers to understand the purpose and usage of each variable. By using descriptive and meaningful names, developers can quickly grasp the intent of the code without needing to decipher cryptic or unclear variable names. This can lead to faster debugging, easier maintenance, and overall better code quality.

// Bad variable naming convention
$a = 10;
$b = 20;
$c = $a + $b;
echo $c;

// Good variable naming convention
$firstNumber = 10;
$secondNumber = 20;
$sum = $firstNumber + $secondNumber;
echo $sum;