What does sm s mean?

Short Message Service (SMS) is a text message service component of telephone, network or mobile communication system. Short message (short message in Taiwan Province province, short message service in Hongkong) and short message service (English SMS) are one of the mobile phone services. This service is sometimes called MESSAGES, short messages and TEXT messages, and there are many common names in English, such as "SMSes, text messages, messages and even text and txts".