SIM, SMS, MMS, E-mail, Voicemail, Video conferencing and Chat

SIM  (Subscriber Identity Module)

 A sim is a tinny computer cheap card that gives a cellular device its unique phone number.  It contains all the credentials which important to connect to any cellular network. Current SIMs typically have 16 to 64 kb of memory which used for storing personal phone numbers, text messages, and other data.

SMS  (Short Message Service)

SMS is the transmission of short text messages to and from a mobile phone, fax machine, and other devices. The message must be no longer than some fixed number of alphanumeric characters and contain no images or graphics.

MMS  (Multimedia Message Service)

It is a standard messaging service to send multimedia content to and from any mobile phone over Cellular network. This includes images, videos, and sound files.

E-mail  (Electronic mail)

It allows you to send and receive messages to and from anyone with an email address anywhere in the world. Email address is a unique address for every user, required to receive and send emails. Photos documents and other files can be attached to an email so that more information can be shared.

Voicemail

A Voicemail system is a Computer Based system that allows users and subscribers to exchange personal voice messages.

Video Conferencing

A technology that allows users in different locations to hold face to face meetings without having to move to a single location.

Chat

Online textual talk in real-time is called chatting. In chatting we type a message on our screen, which is immediately received by the recipient then the recipient can type a message in response to our message which is received by us instantly.

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