Security means achieving correctness of the result of the computation while keeping the players inputs private, even if some of the players cheat. Secure multi party computation can alternatively, and more generally, be seen as the problem of performing a task among a set of players that is specified by involving a trusted party, where the goal of the protocol is to replace the need for the trusted party. Complexity and Security of Distributed Protocols . PhD thesis, Columbia University, 1993. Nevertheless they want to compute some agreed function of their inputs in a secure way.
Security here means maintaining correctness of the output while keeping the players inputs private.
There exists a rich literature on the subject. These approaches can be classified according to a number of criteria that are briefly discussed below. Franklin, M. K. Complexity and Security of Distributed Protocols . PhD thesis, Columbia University, 1993.