Gateway games generally have simple rules that are easy to teach non-gamers in order to attract new players into board gaming as a hobby. But they are great even for seasoned gamers to start off your game night or play between heavier games.
Sushi Go Party!
Dominion (Second Edition)
Lost Cities Card Game with 6th Expedition
Ticket To Ride
Jaipur (New Edition)
Hero Realms: Deckbuilding Game
Skull & Roses: Skull
Dominion: Hinterlands Expansion
Dominion: Empires Expansion
Dominion: Big Box 2nd Edition
Forbidden Desert: Thirst for Survival
Century: Spice Road
Clank! In! Space! - Ding & Dent
Tsuro: The Game of the Path