If you have German permanent residence (Niederlassungserlaubnis), you can live, work, study and start a business in Germany. It's sometimes called a settlement permit.

Permanent residence is better than a residence permit, because you never need to renew it. It lets you stay in Germany permanently, even if you don't work or study.

Permanent residence is not as good as citizenship. It does not let you vote. You can still get deported. Your permanent residence expires if you leave Germany for more than 6 months.

There are two types of permanent residencies: the German permanent residence (Niederlassungserlaubnis), and the EU permanent residence (Erlaubnis zum Daueraufenthalt-EU). They have different requirements.1

Sources and footnotes
  1. berlin.de