Verizon Lowell McAdamREUTERS/Rick WilkingEverything old is new again, and unlimited data plans are back in vogue.

With Verizon returning to the fray this week, all four of the major mobile carriers in the US now advertise unlimited offerings.

But, per usual, each of those plans comes with a significant slate of caveats.

So to help you sort through the fine print, here’s a quick rundown of how this revived set of unlimited plans match up.