A laptop computer is a personal computer for mobile use. It has most of the same components as a desktop computer, including a display, a keyboard, a pointing device such as a touchpad (also known as a trackpad) and/or a pointing stick, and speakers into a single unit. A laptop is powered by mains electricity via an AC adapter, and can be used away from an outlet using a rechargeable battery. Laptops are also sometimes called notebook computers, notebooks, ultrabooks or netbooks. This could also be referred to as portable computers as they are easy to carry around.