What role does the isset() function play in PHP and how can it be utilized to prevent errors in variable handling?

The isset() function in PHP is used to determine if a variable is set and is not NULL. This function can be utilized to prevent errors in variable handling by checking if a variable exists before trying to use it. This helps avoid undefined variable errors and allows for more robust and error-free code.

// Example of utilizing isset() to prevent errors in variable handling
if(isset($variable)){
    // Variable exists and is not NULL, safe to use
    echo $variable;
} else {
    // Variable does not exist or is NULL
    echo "Variable is not set";
}