General Motors just made a move that it says will help get self-driving cars in driveways faster and cheaper.
The automaker bought a small startup called "Strobe" that specializes in technology called Lidar.
Experts say it's key to self-driving cars and uses lasers to build 3D maps of the world.
Other companies have invested in Lidar as well. It's expensive and analysts say acquiring a company that specializes in it could be huge.
