By now, Google's cars have driven down roads around the world -- and in some places, they're sparking concerns about just what information they are collecting.

So the Internet-search giant is opening up a bit about the data it compiles. Google is trying to address criticisms that have been leveled against it in European countries in particular and provided details about Street View cars in a post on its European Public Policy Blog on Tuesday. The company said it had discussed the information before but that it wanted to...