What is a PDA?

PDA is an acronym for Personal Digital Assistant. PDAs are small handheld computers, designed to be very portable and relatively rugged. Many PDAs have a touchscreen interface, operated via a small plastic pen called a stylus, and four to 12 hardware buttons. Some models have a small keyboard in lieu of, or in addition to, the touchscreen. The PDA's main function is it's PIM, usually consisting of a contact manager, a calender application, a note-taking application, and a task manager. Common optional features of a PDA include 8 to 256 MB of storage, desktop PIM synchronization software, and a basic office suit. Additionally, most newer PDAs have SD and/or CF card slots, an infrared port, and wireless connectivity in the form of bluetooth or wifi.

As data entry is a central PDA function, touchscreen-equipped PDAs usually have some form of handwriting recognition software to ease the task. This software can be as simple as block-letter only recognition, or as complex as cursive multi-language recognition. Many models offer a choice of handwriting recognition options, and some have the ability to learn their user's specific handwriting. Other data entry options include speech recognition and a detachable external keyboard. While speech recognition is generally problematic, especially in loud environments, an external keyboard is often a cumbersome accessory for a PDA. The keyboard may be over twice the size of the PDA itself, and requires a flat, stationary surface for placement. Infrared keyboards also require a steady line of sight with the PDA, a feat that is often difficult to achieve in the conditions in which a PDA is designed to operate. For instance, a city bus is not only too loud for speech recognition, but often too unstable for a keyboard or even touchscreen operation.

Most PDAs have programmable interfaces and can run third-party applications. List managers and extended PIM applications are common add-on software for a PDA, as are graphing calculators and photo albums. Computer games are very popular at PDA software download websites, and on wifi-equipped models a web browser may be used to download them directly to the device. Hardware accessories such as GPS receivers can enable a PDA to function as a satellite navigation device, with these being built into high-end models. Digital cameras are also becoming popular in high-end PDAs, which can record both video and still images.