The actress rocked a lob hairdo full of twists and a black and white striped bikini. Nyong'o paired her swimsuit with a denim jacket and round sunglasses to complete the look while lounging by the pool. 

lupitanyongo/Instagram
Alexis Bennett
Jul 05, 2017 @ 1:30 pm

There's no season quite like summer to celebrate the bikini! The two-piece swimsuit may have been popularized on July 5, 1946, but there's actually proof that the sexy styles were worn during the 4th century—according to Roman mosaics at least. But in the modern era, it took years for the scandalous fashion to really catch on.

It wasn't until the effects of war rationing caused the United States government to order manufacturers to cut back on the amount of fabric used to create swimming suits. (See, fashion and function do get along!) Louis Réard, a French engineer, recognized an opportunity to capitalize on the itsy-bitsy pieces and coined the new look the bikini. Ever since two-piece swimsuit has continued to evolve into a staple and summertime must have.

VIDEO: The Evolution of the Swimsuit

We've seen modest versions emerge like the tummy covering tankinis and daring silhouettes like the revealing mini micro bikinis. And although some of the unique bikini trends may not have withstood the test of time, the two-piece swimwear look has become a classic—not to mention the look celebs wear when posting Instagram pics of their toned bikini bodies.

RELATED: How to Find the Right Swimsuit for Your Body Type

In honor of the iconic style's official birthday, we've gathered a gallery of our favorite stars showing off their beach-ready style. Click here to see how the celebs dress for some waterside fun.

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