How can undeclared variable errors be prevented in PHP scripts?

Undeclared variable errors in PHP scripts can be prevented by properly initializing variables before using them. This can be done by declaring variables with default values or checking if they are set before using them in the code.

// Example of preventing undeclared variable errors in PHP
$variable = ""; // Initialize the variable with a default value

if(isset($variable)) {
    // Use the variable safely here
    echo $variable;
} else {
    echo "Variable is not set.";
}