A tablet computer, or simply tablet, is a complete mobile computer, larger than a mobile phone or personal digital assistant, integrated into a flat touch screen and primarily operated by touching the screen. It often uses an onscreen virtual keyboard or a digital pen rather than a physical keyboard.
Electrical devices with data input and output on a flat information display have existed as early as 1888. Throughout the 20th century many devices with these characteristics have been ideated and created whether as blueprints, prototypes or commercial products, with the Dynabook concept in 1968 being an spiritual precursor of tablets and laptops. During the 2000s Microsoft attempted to define the tablet personal computer (tablet PC) product concept as a mobile computer for field work in business, though their devices failed to achieve widespread usage due mainly to price and usability problems that made them unsuitable outside of their limited intended purpose. In April 2010 Apple Inc. released the iPad, a tablet computer with an emphasis on media consumption. The shift in purpose, together with increased usability, battery life, simplicity, lower weight and cost, and overall quality with respect to previous tablets, was perceived as defining a new class of consumer device and shaped the commercial market for tablets in the following year.
The term may also apply to a variety of form factors that differ in position of the screen with respect to a keyboard. The standard form is called slate, which does not have an integrated keyboard but may be connected to one with a wireless link or a USB port. Convertible notebook computers have an integrated keyboard that can be hidden by a swivel joint or slide joint, exposing only the screen for touch operation. Hybrids have a detachable keyboard so that the touch screen can be used as a stand-alone tablet. Booklets include two touch screens, and can be used as a notebook by displaying a virtual keyboard in one of them.
The iPhone 4 is a touchscreen smartphone developed by Apple and designed by Jonathan Ive. It is the fourth generation of iPhone, and successor to the iPhone 3GS. It is particularly marketed for video calling (marketed by Apple as FaceTime), consumption of media such as books and periodicals, movies, music, and games, and for general web and e-mail access. It was announced on June 7, 2010, at the WWDC 2010 held at the Mascone Center, San Francisco, and was released on June 24, 2010, in the United States, the United Kingdom, France, Germany and Japan.
The iPhone 4 runs Apple's iOS operating system, the same operating system as used on previous iPhones, the iPad, and the iPod touch. It is primarily controlled by a user's fingertips on the multi-touch display, which is sensitive to fingertip contact.
The most noticeable difference between the iPhone 4 and its predecessors is the new design, which incorporates an uninsulated stainless steel frame that acts as the device's antenna. The internal components of the device are situated between two panels of chemically strengthened aluminosilicate glass. It has an Apple A4 processor and 512 MB of eDRAM, twice that of its predecessor and four times that of the original iPhone. Its 3.5-inch (89 mm) LED Backlit liquid crystal display with a 960×640 pixel resolution is marketed as the "Retina Display".
The latest operating system release is iOS 4.3.5 (for GSM) and 4.2.10 (for CDMA).
ARM is a 32-bit reduced instruction set computer (RISC) instruction set architecture (ISA) developed by ARM Holdings. It was known as the Advanced RISC Machine, and before that as the Acorn RISC Machine. The ARM architecture is the most widely used 32-bit ISA in terms of numbers produced. Originally conceived by Acorn Computers for use in its personal computers, the first ARM-based products were the Acorn Archimedes range introduced in...