Mobile data is not turned on, what is it?

Have a few days this sign on my Huawei, which looks like I have the mobile data function, but I have not. I turned on my WLAN, nothing more. And where now this sign is (picture follows), was usually always the percentage of my battery! What's this?

This means that the mobile reception is currently very, very bad for you.

2G means the data transfer works via GSM and has max. 9.6 kbps, max. But 236 kbit / s if your phone synonymous with 2G 2.75G, so EDGE means.