In this example, we first define the user ID and the new first name for the user. We then connect to the database using the mysqli_connect function and build a SQL UPDATE query to update the user's first name. We execute the query using the mysqli_query function and close the database connection using the mysqli_close function. The setFirstName function is typically included in an application's user class or model. It is part of the core PHP library and does not require any additional packages or libraries.