Waiters first appeared in The Sims: Hot Date and reappeared in The Sims 2: Nightlife and The Sims 4: Dine Out. They are NPCs that serve meals in restaurants on community lots. In Hot Date, they cannot be interacted with. In The Sims 2, some interactions include: Order, Order for (name), and Order for Group. They will take the Sims' order and give it to the chef. Otherwise, they will clean drinking glasses or take orders of other customers. On occasion, they will drop their serving platter on a Sim while they are sitting, though the likelihood of this happening increases drastically if the Waiter has a strong negative relationship with the Sim they are serving. Having food dropped on them will give the Sim a negative memory. Like any other NPC in The Sims 2, Sims can can have relationships with them. They cannot be tipped in The Sims 2.
In Hot Date, each podium in a restaurant will spawn a waiter or waitress. In The Sims 2, there is usually only one in a restaurant, but larger restaurants may have more.