Paul Rosenzweig has a fantastic article about the different types of encryption and what each means from a legal standpoint. There are a lot of services that will tell you your data is encrypted, but if the service is still holding the keys to that encryption then your data may not be encrypted from legal bodies who could compel that service provider to turn over your encryption keys.
I think this is of utmost importance to understand right now. Far too many people, not only don’t understand the difference, but they are misled by marketing bullshit on “cloud” service providers websites when they refer to encryption. At the end of it all, right now, the only stuff that is truly encrypted are the things that are also a big pain in the ass to use.1
As a rule of thumb. ↩