USSD (Unstructured Supplementary Service Data):-

                USSD is also referred to as Quick Codes or “Feature codes”. It is a communications protocol used by GSM cellular telephones to communicate with the mobile network operator’s computers. It is a technology platform through which information can be transmitted through a GSM network on a basic phone and will be available on all mobile phones with SMS facility. To used USSD, users will have to dial *99# to get the mobile balance. This service allows mobile banking transactions using basic feature mobile phone, there is no need to have mobile internet data facility for using USSD based mobile banking.