SMS stands for Short Message Service. It is a text messaging service that allows mobile devices to exchange short text messages using standardized communication protocols. An SMS can contain up to 160 characters and is sent using a cellular signal. It is different from MMS (Multimedia Messaging Service), which allows for the inclusion of pictures, audio clips, or videos in addition to text. SMS is widely used for personal and business communication, and it is a key component of mobile marketing and machine-to- machine communication