Research in Motion makes RIM and Blackberry wireless handheld
models for a variety of applications and personal preferences,
including an OEM version. Some models are primarily for
Internet email, whereas other models include the functionality
to run application software such as calendars, address books,
and much more. The devices fit in the palm of a user’s hand and
are lightweight. Wireless communications is through one of two
different networks, Mobitex or DataTAC (Ardis Network).
Both Mobitex and DataTAC are packet-switched, narrowband
PCS networks designed for wide-area wireless data communication
at a data rate of 19.2 Kbps. They provide always-on connections
with extensive coverage and in-building penetration,
seamless roaming, fast messaging, high reliability, and advanced
messaging services. Dialing up to retrieve emails is unnecessary.