Honorary work ("Ehrenamt") is employment for charitable organisations without a wage or with only a very low wage. You do not need any work permit for this work. If you are not sure whether these conditions have been met or whether your employment actually constitutes a job or internship, consult your immigration authority ("Ausländerbehörde").
Honorary work: a good way to find a proper job
Volunteering is highly regarded in Germany. Volunteers usually take on important tasks, for example in helping new refugees. They distribute clothes and food, teach German or help children in the accommodation centres. If you already speak some German, have not yet found a job and think you can help other people, then you should contact the staff of the aid organisations. Helpers are always needed and sometimes this can lead to opportunities for a paid job later on.