Pager

A pager, also called a beeper or bleeper, is a wireless telecommunications device that receives and displays alphanumeric or voice messages. One-way pagers can only receive messages, while response pagers and two-way pagers can also acknowledge, reply to, and originate messages using their own internal transmitter. Pagers were developed in the 1950s and 1960s and became widely used from the 1980s through the early 2000s, and although the spread of mobile phones and smartphones has greatly reduced their everyday use, pagers are still used by some emergency services because paging network coverage can remain more reliable than cellular networks during disasters.