The full form of USSD is Unstructured Supplementary Service Data. It is a technology used for sending text messages between a mobile phone and an application or a computer program. It is a real-time and menu-based communication channel that is used for various purposes such as balance inquiries, mobile banking, and other services. Unlike other messaging technologies, such as SMS and MMS, USSD messages do not require a mobile data connection or a GPRS connection. Instead, they are sent over a voice channel and are instantly processed by the network.
USSD was first introduced in the early 1990s as a way to access various services, such as voicemail, without the need for a mobile data connection. Since then, it has evolved and is now widely used for a variety of purposes, including mobile banking, payment services, and other financial transactions. It is especially useful in developing countries where mobile data connections are not widely available or are not reliable.
USSD codes are usually accessed by dialing a specific combination of numbers, starting with the * symbol, followed by the code. The code is then sent to the network, which processes the request and returns the appropriate response. USSD messages are quick and secure, making them an ideal choice for financial transactions and other sensitive information.
In conclusion, USSD technology is an important tool for communication between mobile phones and applications. Its real-time and menu-based nature, along with its simplicity and security, make it a popular choice for various services, including mobile banking and payment services, in developing countries.