A subnotebook or an ultraportable, is a laptop designed and marketed with an emphasis on portability (small size, low weight, and often longer battery life). Subnotebooks are usually smaller and lighter than standard laptops, weighing between 0.8 and 2 kg (2-5 lb), with a battery life exceeding 10 hours.
Since the introduction of netbooks and ultrabooks, the line between subnotebooks and either category has blurred. Netbooks are a more basic and cheap type of subnotebook, and while some ultrabooks have a screen size too large to qualify as subnotebooks, certain ultrabooks fit in the subnotebook category. One notable example of a subnotebook is the Apple MacBook Air.