RIM (Research in Motion) is the company behind the famous BlackBerry phone. The core function of a BlackBerry smartphone is primarily sending and receiving e-mail and BlackBerry's are widely regarded as the best and most efficient mobile device for business and corporate e-mail.
The first traditional BlackBerry phone was released in 2003 and there have been plenty of BlackBerry phones since then.
Early BlackBerry phones consisted of a small, non-touchscreen with a physical QWERTY keyboard which made it easy to type long blocks of text. Current BlackBerry models combine a touchscreen with a physical keyboard, though some have done away with a keyboard to include a full touchscreen.
Popular BlackBerry models include the Bold, the Curve and more recently, the Torch. The latter combines a full touchscreen with a physical, QWERTY keyboard, though another variant of the Torch does away with the keyboard completely in order to use a touch-only interface.
While BlackBerry phones are still sold, their popularity has dwindled with the rise of iPhone and Android phones. You should consider a BlackBerry if you don't like the idea of typing on a touchscreen keyboard. BlackBerry handsets are widely regarded as having the best keyboard.