base64_decode(string $string, bool $strict = false): string|false
// Example
// base64_decode('VGhpcyBpcyBhIHN0cmluZw==')
// Result: This is a string
// For Encoding
base64_encode(string $string): string
// base64_encode('This is a string')
// Result: VGhpcyBpcyBhIHN0cmluZw==