Crews are setting up booths in the exhibit halls and companies are giving sneak peeks at their latest creations.
There are eye-catching curved televisions, but they may have some bugs to work out. There are Ultra-HD sets - a super sharp picture some call the future of TV. Of course, people said that about 3D TVs a few years ago.
People are also buzzing about drones.
Some of the drones come from Silicon Valley startups. There are twice as many startups at CES as just a couple years ago.
Some are excited over the tiniest wearable technology and some is over the biggest gadget of all, cars.
Audi showed off a car that drives itself - up to 40 miles an hour, as long as you don't have to change lanes. It's a work in progress. Meanwhile, Chevy is turning automobiles into a 4G hotspot. And the latest Corvette shoots HD video.
General Motors and Audi are working with Google to build cars that run Android, the smartphone operating system.