SMS (Short Message Service) is one of the oldest and most common methods of mobile communication. It allows sending of short (160 character) text messages between mobile devices. The first SMS message was sent in 1992. By the 2000s, the average number of texts sent per month increased dramatically to 35 per person in the US. While SMS was hugely popular, its use has declined in recent years with the rise of mobile messaging apps like WhatsApp that allow messaging over data networks. SMS remains an important communication method supported on major mobile technologies worldwide.