What exactly is Bcc?

Bcc stands for Blind Carbon Copy. It's a field, just like the To-field in your e-mail application/service. The difference is that the addresses you send the e-mail to are hidden and can't be seen by anyone but the original sender. Read on to learn about the correct use of the Bcc-field and how to use it in your e-mail application.

But my e-mail application doesn't have a Bcc-field?

Yes, it does. In many applications the Bcc-field is hidden and you need to choose to show it. It's usually very easy to turn on.
We think that it's very stupid to hide it per default, but some people at some big companies decided that it was confusing with too many fields. You can turn it on. See How to use Bcc in... to get a guide on how to use it in your application/service.