Monday is the first day for NFL teams to lay the 'franchise tag' on players, which essentially gives the team a guaranteed one year contract for any one player that they want. That usually comes in handy for free agency when there is a contract dispute going on, keeping UFA's away from other teams that might want to snatch them up in FA.
The Cleveland Browns are lucky enough to not have any real contract disputes, except for the fact that they have yet to finally work something out with D'Qwell Jackson. Jackson will be the likely candidate for the Franchise Tag in Cleveland if they can't, though both parties want Jackson to stay with the Browns.
Jackson was a rock at the center of the Cleveland defense in 2011, gaining 158 tackles and a fistful of sacks at the MLB position. He's probably the number one priority for Cleveland to get back on the team in the offseason, the biggest reason why the Franchise Tag might be considered.