I have a question concerning the word potluck. I look it up in the WordReference dictionary but I am still confused. I would like to know what is happening during a potluck. Thank all in advance. Here is a context:
Potluck for Mr. A is this Friday! Sign up sheet is in office area somewhere. Donate as much or as little as you prefer by Thursday at 3:00. The idea is to buy Mr. A a few different gift cards for tech stores and restaurants since Mr. A likes tech toys and food.