Change record status: 
Project: 
Introduced in branch: 
8.x
Introduced in version: 
8.0
Description: 

Languages used to be stored and maintained in the database. Deploying new languages or translating language names to other languages was not possible. In Drupal 8, languages are now stored with the configuration system.

The most important immediate change for Drupal 8 is that languages are now created with the language code / machine name universally named "id" like any other configuration entity. Prior to this change in Drupal 8:

<?php
use Drupal\language\Language;
$language = new Language('langcode' => 'de');
$langcode = $language->langcode;
?>

After this change in Drupal 8:

<?php
use Drupal\language\Language;
$language = new Language('id' => 'de');
$langcode = $language->id;
?>
Impacts: 
Module developers
Updates Done (doc team, etc.)
Online documentation: 
Not done
Theming guide: 
Not done
Module developer documentation: 
Not done
Examples project: 
Not done
Coder Review: 
Not done
Coder Upgrade: 
Not done
Other: 
Other updates done