CODE EXAMPLE FOR PHP

wp+ theme translate

function myfirsttheme_setup() {
 
    /**
     * Make theme available for translation.
     * Translations can be placed in the /languages/ directory.
     */
    load_theme_textdomain( 'myfirsttheme', get_template_directory() . '/languages' );
    }
    add_action( 'after_setup_theme', 'myfirsttheme_setup' );