I PAD

History

Steve Jobs, Apple CEO, introducing the iPad.Apple's first tablet computer was the Newton MessagePad 100 introduced in 1993, which led to the creation of the ARM6 processor core with Acorn Computers. Apple also developed a prototype PowerBook Duo-based tablet, the PenLite, but in order to avoid hurting Message Pad sales did not sell it Apple released several more Newton-based PDAs, and discontinued the last, the MessagePad 2100, in 1998.

Apple re-entered the mobile-computing market in 2007 with the iPhone. Smaller than the iPad but featuring a camera and mobile phone, it pioneered the multitouch finger-sensitive touchscreen interface of Apple's mobile operating system—iOS. By late 2009, the iPad's release had been rumored for several years. Mostly referred to as "Apple's tablet", iTablet and iSlate were among the speculated name. The iPad was announced on January 27, 2010 by Steve Jobs at an Apple press conference at the Yerba Buena Center for the Arts in San Francisco.

Screen and Input

The iPad's touchscreen display is a 25 cm (9.7 in) liquid crystal display (1024 × 768 pixels) with fingerprint-resistant and scratch-resistant glass. Like the iPhone, the iPad is designed to be controlled by bare fingers; normal gloves and styli that prevent electrical conductivity may not be used, although there are special gloves and styli designed for this use.

The display responds to two other sensors: an ambient light sensor to adjust screen brightness and a 3-axis accelerometer to sense iPad orientation and switch between portrait and landscape modes. Unlike the iPhone and iPod touch built-in applications, which work in three orientations (portrait, landscape-left and landscape-right), the iPad built-in applications support screen rotation in all four orientations (the three aforementioned ones along with upside-down), meaning that the device has no intrinsic "native" orientation; only the position of the home button changes.

The iPad has a switch to lock out this screen rotation function (reportedly to prevent unintended rotation when the user is lying down).There are a total of four physical switches, including a home button below the display that returns the user to the main menu, and three plastic physical switches on the sides: wake/sleep and volume up/down, along with the screen rotation lock.

Connectivity

The iPad can use Wi-Fi network trilateration from Skyhook Wireless to provide location information to applications such as Google Maps. The 3G model contains A-GPS to allow its position to be calculated with GPS or relative to nearby cellphone towers; it also has a black plastic accent on the back side to improve 3G radio sensitivity.For wired connectivity, the iPad has has a dock connector; it lacks the Ethernet and USB ports of larger computers.

Applications

The iPad comes with several applications, including Safari, Mail, Photos, Video, YouTube, iPod, iTunes, App Store, iBooks, Maps, Notes, Calendar, Contacts, and Spotlight Search. Several are improved versions of applications developed for the iPhone.

The iPad syncs with iTunes on a Mac or Windows PC.Apple ported its iWork suite from the Mac to the iPad, and sells pared down versions of Pages, Numbers, and Keynote apps in the App Store.Although the iPad is not designed to replace a mobile phone, a user can use a wired headset or the built-in speaker and microphone and place phone calls over Wi-Fi or 3G using a VoIP application.

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