I think if you are a laptop repair shop owner, you will see why Brett don't call a laptop as a PC (yes, I would agree laptop is a class of PC).
From his perspective and for his purpose, if he advertise that he fixes PC, then there will be loads of people calling up to get his shop to fix their desktop, as well as laptop. He needs to make that distinction for the purpose of his shop. that's why he wrote:
"Not in my Computer shops they arent... "
Try to understand from other people's perspective and the world is a happier place.
BTW, this thread is now off topic and will be close soon.
@PO, if you would like to check whether your laptop meet the system requirement of Sims 3, you can either go to the official site and compare it for yourself, or if you are not familiar with hardware and don't know what to compare, just make another post with the question and there will be plenty of people here to answer your question.