Chapter 13: Internationalization and Languages
In this chapter, we are going to talk about the internationalization and multilingual features in Drupal 9 from the point of view of a module developer. Many of the built-in capabilities of this system are oriented toward site builders—enabling languages and translating content and configuration entities, as well as the Drupal interface (for administrators and visitors alike). Our focus will be what we as module developers need to do programmatically to ensure that site builders and editors can use the aforementioned features. To that end, this chapter will be more of a reference guide with various tips, techniques, and even rules we need to follow when writing our code. Notwithstanding, we will also talk a bit about how we can work with languages programmatically.
First, however, we will start with an introduction to the multilingual ecosystem that comes out of the box and the modules responsible for various parts of it.
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