What are the best practices for utilizing isset() and !empty() functions in PHP code?

When working with PHP code, it is important to properly handle variables that may not be set or may be empty. The isset() function checks if a variable is set and not null, while the !empty() function checks if a variable is not empty. It is a good practice to use isset() to check if a variable is set before using it to avoid potential errors, and then use !empty() to check if the variable has a non-empty value.

// Check if a variable is set and not empty before using it
if(isset($variable) && !empty($variable)) {
    // Variable is set and not empty, proceed with using it
    echo $variable;
} else {
    // Variable is not set or empty, handle this case accordingly
    echo "Variable is not set or empty";
}