A tablet is a mobile device equipped with a touch-screen, usually between five and 10in in size.
The tablet market is largely divided into two categories; Windows-based tablets that are effectively portable PCs with a touch-screen, and other devcies such as Apple's iPad that are based on mobile oeprating systems derived from smartphones.
Windows-based tablets may themselves be slate-mode devices with no keyboard, or convertibles, which resemble a laptop but the screen can be folded over the keyboard and used like a slate.
The second type of tablet tends to be smaller and lighter. There are a number of these on the market, with the iPad and the Android powered Samsung Galaxy Tab being the most popular. Some are also able to double as a smartphone by offering voice calling.
The success of the tablet form factor led to Google redesigning its Android operating system from the ground up for use on the devices. Android 3.0 Honeycomb will debut on the Motorola Xoom and will ship on the Galaxy Tab 2.
Other notable devices incoming in 2011 include the HTC Flyer, running on Android 2.3 Gingerbread and the HP TouchPad which will come with the webOS operating system.
