What do GmbH/AB mean?

Sometimes I see companies with names such as
Straight Dope GmbH or Straight Dope AB.
Can someone tell me what these letters after the name mean.

GmbH (Gesellschaft mit mit beschränkter Haftung) is the German equivalent of a limited liability company, and predates other LLCs with a first appearance in 1892 (according to sites I’ve been looking at). Also used in Austria and Switzerland.

A/B (Aktiebolag) is roughly the Swedish for Limited Company. I think it may also be used in Finland too.

Slight typo above; only one mit in GmbH.

<semi-hijack>
How about AG?
</semi-hijack>

Aktiengesellschaft (AG):

More on GmbH:

(from this page)

Finland, as you may know, has two official languages: Finnish and Swedish. So both AB and its Finnish equivalent, OY are used, sometimes at the same time. The classic example is the Finnish state wine-and-spirits monopoly, which I swear I’ve seen written as OY Alko AB.