Wikipedia - Blackberry

The BlackBerry is a wireless handheld device introduced in 1999 which supports push e-mail, mobile telephone, text messaging, internet faxing, web browsing and other wireless information services. Developed by the Canadian company Research In Motion (RIM), it delivers information over the wireless data networks of mobile phone service companies. BlackBerry first made headway in the marketplace by concentrating on e-mail. RIM currently offers BlackBerry e-mail service to non-BlackBerry devices, such as the Palm Treo, through the BlackBerry Connect software. The original BlackBerry device had a monochrome display, but all current models have color displays. While including the usual PDA applications (address book, calendar, to-do lists, etc.) as well as telephone capabilities on newer models, the BlackBerry is primarily known for its ability to send and receive e-mail wherever it can access an atmosphere wireless network of certain cellular phone carriers. It has a built-in keyboard, optimized for "thumbing", the use of only the thumbs to type. System navigation is primarily accomplished by the trackwheel (or "thumbwheel"), a scrolling wheel with a "click" function, located on the right side of the device. Newer models are now utilizing a trackball in the middle of the device as Research In Motion has moved from the trackwheel to the trackball. Some models (currently, those manufactured for use with Nextel, TELUS, AT&T, and other iDEN networks) also incorporate a two-way radio. Some BlackBerry devices don't depend on mobile phone service coverage and are Wi-Fi compatible like similar handheld devices that are on the marketplace.

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