PAGER

A pager (sometimes called a beeper or bleep) 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 1990s, pagers fulfilled the role of common personal and mobile communications. Today, pagers mainly support the "critical messaging" markets. They are the ideal solution for very quick, very reliable personal or group messaging. Unlike many other mobile communications networks, they continue to work in times of emergency or disaster as they do not suffer from network overload as has been proven many times (September 11 attacks, Hurricane Katrina). For this reason, they are still very popular with emergency service personnel, medical personnel, and information technology support staff.

Paging is a subscription service offered in a variety of plans and options to meet the needs of a subscriber and the type of device used. In general, all pagers are given unique phone numbers while alphanumeric pagers are given an email address, usually consisting of the phone number.

Pagers also have privacy advantages compared with cellular phones. Since a one-way pager is a passive receiver only (it sends no information back to the base station), its location cannot be tracked. However, this can also be disadvantageous, as a message sent to a pager must be broadcast from every paging transmitter in the pager's service area. Thus, if a pager has nationwide service, a message sent to it could be intercepted by criminals or law enforcement agencies anywhere within the nationwide service area.Upon calling a phone number assigned to a pager, the calling party reaches a recorded greeting asking the caller to enter a numeric message, and sometimes giving the caller an option to leave a voice mail message. Generally, the paged person will receive an alert from the pager with the phone number to return the call and/or a pager code within a few minutes. In the case of email paging, the text is displayed. Pagers are still in use today in places where mobile phones typically cannot reach users, and also in places where the operation of the radio transmitters contained in mobile phones is problematic or prohibited. One such type of location is a large hospital complex, where cellular coverage is often weak or nonexistent, where radio transmitters are suggested to interfere with sensitive medical equipment and where there is a greater need of assurance for a timely delivery of a message.