Pager is a Simplex Communication Device. Paging Systems are communication systems that send messages to a subscriber. Message can be numeric or alphanumeric.

Paging Systems are used to notify a subscriber of the need to call a particular telephone number or to travel to a location to receive further instructions. In modern paging systems, news headlines, faxes can also be sent.

A message is sent to a paging subscriber via the paging system access number with a telephone keypad or modem. The issued message is called a "Page‟. The paging system then transmits the page throughout the service area using base stations which broadcast the page on a radio carrier.

The coverage area of a simple paging system ranges from 2 to 5 km while a wide paging system can have a worldwide coverage area. Whenever a sender wants to send a message to a receiver he dials the 10 digit pager number of receiver through his telephone.

Then this call is accepted by the operator present in the paging control centre to whom the receiver pager number and the message to be sent has to be sent.

Then the operator will broadcast the message and the receiver paging number to all the paging terminals or the base stations.

Then a particular base station under the area where the receiver is present will transmit the message to the receiver pager. Then the receivers pager device will receive all messages and will verify whether the sender number is stored in its memory or not.

If it is stored then the pager device will give beep which indicates the receiver that a message is sent by sender to his pager and the message will be displayed in the LCD.