How can proper variable articulation and documentation improve code readability and understanding in PHP?

Proper variable articulation involves using descriptive and meaningful names for variables to convey their purpose clearly. Documentation, such as comments, can also be added to explain the purpose of variables and code sections. This improves code readability and understanding for developers who work on the code in the future.

// Bad variable names and lack of documentation
$a = 10;
$b = 20;

// Good variable names and documentation
$firstNumber = 10; // Represents the first number in the calculation
$secondNumber = 20; // Represents the second number in the calculation