Internationalization and Localization

When you are developing WordPress themes and plugins, you should have the scope of your website and its audience in your mind. By doing so, you can help people translate your work into other languages. This is known as internationalization – abbreviated as i18n in WordPress.

And the process of translating an internationalized theme or plugin to another language is known as localization – abbreviated as l10n.

By internationalizing your theme or plugin, you are making way for other people who are proficient in other languages to translate your plugin into their language. This allows your code to be used by people who rely on those languages to manage their WordPress sites. You can read more about it from Internationalization handbook page.