I've invited people for drinks, and they've expected dinner. I've invited people for dinner, and they've shown up already "having had." What time means drinks, and what time means dinner?

For a cocktail party on a Friday night, start at 6 or 6:30, so people can come straight after work and go for dinner afterward, says Gary Arabia, a Los Angeles caterer and chef-owner of Global Cuisine. A Saturday night cocktail party can start later, Arabia says, adding that cocktail parties around the dinner hour are OK, as long as your invitation makes clear that dinner will not be served. Weekend dinner parties generally start between 7 and 8. Having drinks first allows all your guests time to arrive; let your invitation convey the details: "7 P.M. cocktails, 8 P.M. dinner."