A 3-6 digit number which enables sending and receiving of SMS messages, usually in SMS sweepstakes, polling, TV voting etc. With short codes, sending and receiving messages is limited to national borders. They can be leased from mobile network operators or through specialised messaging companies that also provide consultancy and tech support. Dedicated short codes are used by one company only, while shared ones can be used by more companies, which have their campaigns distinguished by keywords. For example, one company can use the number to receive SMS messages with the SUPPORT keyword, and the other company can use it to receive messages with the PIZZA keyword. These keywords allow the matching of inbound messages with appropriate campaigns.