This article relates to Jackbox Games such as the You don't know Jack, Jackbox Party Packs, Fibbage XL, QuipLash and Drawful 2.
Note: This article does not apply the "YOU DON'T KNOW JACK Classic Pack".
These games are downloaded to and played on your PC through Steam.
After adding the game to your Steam library, start the Steam program on your PC, select the Jackbox game in your Steam game library and click the Install/Play button to star the game.
Each time you restart the game on your PC it will display a new unique "Room Code".
Each game player then browses to https://jackbox.tv/ on their personal Internet connected devices (e.g. Smartphone, Tablet or PC) and enters the "Room Code" with their name to join the game.
When all players have joined the game, one play taps/clicks the "Everybody's in" button and the game starts with each player using their personal devices to play.
Jackbox Games provide some more information, and a video at the following web-page:
But you can watch the Jackbox Games video below: