Short codes - also known as short numbers or Common Short Codes (CSC) - are special telephone numbers, significantly shorter than full telephone numbers, which can also be used to address SMS and MMS messages from mobile phones or fixed phones.
They are designed to be shorter to read out and easier to remember than normal telephone numbers. While similar to telephone numbers, they are, at the technological level, unique to each operator, although providers generally have agreements to avoid overlaps.
Short codes are widely used for value-added services such as television voting, ordering ringtones, charity donations and mobile services (such as Google's SMS search service and 57272). Messages sent to short code numbers are generally billed at a higher rate than a standard SMS.