Mobile telephony

Mobile telephony is the provision of wireless telephone services to mobile phones, distinguishing it from fixed-location telephony provided via landline phones. Traditionally, telephony specifically refers to voice communication, though the distinction has become less clear with the integration of additional features such as text messaging and data services. Modern mobile phones connect to a terrestrial cellular network of base stations (commonly referred to as cell sites), using radio waves to facilitate communication. Satellite phones use wireless links to orbiting satellites, providing an alternative in areas lacking local terrestrial communication infrastructure, such as landline and cellular networks. Cellular networks, satellite networks, and landline systems are all linked to the public switched telephone network (PSTN), enabling calls to be made to and from nearly any telephone worldwide. As of 2010, global estimates indicated approximately five billion mobile cellular subscriptions, highlighting the significant role of mobile telephony in global communication systems.