Others are not yet known
The Steam Playground has launched a free game trial service. Unlike demo versions, where there are restrictions directly in the game content, the trial version is limited only by time, otherwise the game is at the complete disposal of the gamer.
The first game was Dead Space
The first game that is available in this mode was the new Dead Space, that is, a remake of the first part of the cult series. In this game, you can spend 90 minutes in trial mode, which is a lot in general. It is likely that other games will be limited to a similar time interval.
Separately, it is worth noting that the time to install the game is not taken into account, because on some other sites this feature has previously taken place.
It is not yet clear what games will be available as trials in the near future and how massive this offer will be.