First served basis là gì

It means whoever arrives to the place gets to do the thing or take up space first. It means supplies are limited and will be used up by the first people that show up. Example: "Parking spots are on a first come first served basis". If all the parking spots are full, nobody who is parked leaves to make space, because the people that came first get to take up the space.

Basicly means when you go to the restaurant ,you come first, you are served first