A laptop is a personal computer designed for mobile use and small and light enough to sit on a person's lap while in use. A laptop integrates most of the typical components of a desktop computer, including a display, a keyboard, a pointing device (a touchpad, also known as a trackpad, and/or a pointing stick), speakers, and often including a battery, into a single small and light unit. The rechargeable battery (if present) is charged from an AC adapter and typically stores enough energy to run the laptop for three to five hours in its initial state, depending on the configuration and power management of the computer.
Laptops are usually notebook-shaped with thicknesses between 0.7–1.5 inches (18–38 mm) and dimensions ranging from 10x8 inches (27x22cm, 13" display) to 15x11 inches (39x28cm, 17" display) and up. Modern laptops weigh 3 to 12 pounds (1.4 to 5.4 kg); older laptops were usually heavier. Most laptops are designed in the flip form factor to protect the screen and the keyboard when closed. Modern tablet laptops have a complex joint between the keyboard housing and the display, permitting the display panel to swivel and then lie flat on the keyboard housing.
