What was the floppy disk in this scene from The Matrix?

I remember in movie The-Matrix when Neo's computer is hacked by Trinity in the beginning of the movie then when Neo tries to delete the message "follow the white rabbit" then all of a sudden there is this banging on the door, and Neo said "Who is this" and the other guy on the door replied "Its troy", then what happened that Neo gave the guy some sort of floppy and told him "If you got caught using that". I am wondering what was on that floppy or whatever it was that made Neo say that?