I've been using laptops for a long time now. Not exclusively, but I've got plenty of experience with them. When it comes to hardware, laptops are nothing like any other systems. They use different motherboards, different graphics cards. Sometimes they use desktop components for things like memory, processors and network cards, but often those are specialized too. Laptops can be broken down into two major catagories: ultra-portable systems, designed for minimal weight and maximum battery life, and "desknotes", often using desktop components, large screens, and powerful graphics systems. I personally prefer desknotes because I like having a lot of power under the hood.