In Prey we can find a total number of different types of collectibles. These collectibles are spread throughout the game, and most importantly, many will only be available at certain times of the game so if you do not get them you will have to do it again in a new game.
Employees of Talos 1 Lobby
E-mails of the Talos 1 Lobby
They are spread over the different computers you will find in the game. If you open a computer and see that in the post section a number appears within a few parentheses (X) is that on that computer you can read a new mail.
These devices will be distributed throughout the game, whether on top of desks, along with a corpses or automatically during the game.