It seems like it would go without saying, but a little black bikini (LBB, if you will) is about as ubiquitous in your wardrobe as that go-to LBD: It never goes out of style and it can easily go from a formal affair (that super-chic pool party you just RSVP’ed) to a low-key bash (your bestie’s backyard rager). If you don’t already have one in the mix, the time to start shopping is now. To make things simple we’ve chosen a handful of styles to go with every kind of vibe—sporty, super-feminine and a few classic cuts in between. Trust us, you won’t know how you ever lived without an LBB.