can't understand _e function well

Question

<?php _e( $text, $domain ) ?>

$domain

(string) (optional) Domain to retrieve the translated text Default: 'default

can't understand the second argument well. when i custom a theme, where the $domain's value shows on the theme, what value should i give it to.? could i write the $domain part optionally?i see some themes using its theme name as the $domain. but the document says Domain to retrieve the translated text.it's not a domain. why? some using other strings which doesn't have any relevance of the theme?

Answer 1

$domain is the unique identifier for retrieving translated strings.

It is set in functions.php

<?php load_theme_textdomain( $domain, $path ) ?>

ex:

load_theme_textdomain('my_theme', get_template_directory() . '/languages');

<?php _e( 'Translate this text', 'my_theme' ) ?>

If you don't have a translation file but want't to make it translatable just define the textdomain.

load_theme_textdomain('my_theme');