There are several differences in the wiring of homes and apartments in China and the States. The first one is that homes in China use 220V, and the states use 110V. That isn’t something you can see, but you may need to know that when you plug in your appliances. Don’t worry about your laptop, because the power cable probably can make the adjustment, so no problem with it.
The lights would be another difference. It is not uncommon at all to see a light in China that doesn’t have a glass globe around it. That is not to say that nice light fixtures aren’t there, it is just to say that frequently you will see just the light socket to hold the light bulb. In fact, sometimes you will see some electrical wire hanging from the ceiling with a socket at the end, and that is the light fixture for the room. 
Another difference is with the unused cables. Sometimes you will come across an electrical outlet or light switch that has some unused cables protruding from them. You never know if they are hot or not, so be careful!
I am not aware of anyone having a problem with being electrocuted by these exposed wires, and that obviously is a good thing. So, if you are traveling in China, don’t be surprised if you encounter wiring like this.