A pager (sometimes called a beeper)
is a simple personal telecommunications device for short messages. A one-way
numeric pager can only receive a message consisting of a few digits, typically
a phone number that the user is then expected to call. Alphanumeric pagers
are available, as well as two-way pagers that have the ability to send and
receive email , numeric pages, and SMS messages.
Until the popular adoption of mobile phones in the late 1990s, pagers fulfilled
the role of common personal and mobile communications. Radio Paging Systems
now are generally for emergency service personnel, medical personnel, and
information technology support staff.
