What is the difference between a Caucus and a Primary?

The difference between a Caucus and a Primary is that in a Caucus, party members are meeting to discuss party issues or policies and voting does not always take place. They are long meeting and members have to stay for as long as necessary to resolve, discuss or vote. In the other hand a Primary is what we know as regular elections. In Primary elections party member vote on select candidates, who will represent the party in a future election.