Salvador is literally surrounded by beaches. They are where people go to relax, cool off, chill, socialize, eat, drink, dance, exercise, surf, and of course swim. They vary from crowded city beaches great for meeting people to tropical idylls up and down the coast.
One of the first beaches that most people get to know in Salvador is Porto da Barra. Porto da Barra was, interestingly, the site of Bahia's first European settlement, Vila Velha, or the Old Village. During the 1960's it was a hangout for Tropicalistas Caetano Veloso (who sang of the beach in his song "Qual é Baiana?") and Gilberto Gil and their crowd, and it continues to be very much of a hangout today.
The beach is set within the bay and the water is much calmer than on the oceanside beaches; it's good for swimming. On weekends, especially Sundays, Porto da Barra can get very crowded, and it's a good idea to keep a good eye on your stuff. Sandals, sunglasses, and like items can disappear in an instant, the magicians usually being innocent-enough looking kids playing around in the sand near you.
Moving out, the next beach is Farol da Barra. Farol means a beacon; here "lighthouse" (the word "farol" is derived from "Pharos", the name of the small island of the coast of Alexandria, Egypt, where a great lighthouse, one of the Seven Wonders of the Ancient World, was built). The end of the beach closest to the lighthouse is rocky, with protected pools making it a good place for kids to safely play in the water. The far end of the beach is usually surfer territory.
The Farol da Barra
From here the beaches run in a more-or-less solid line up to, oh I don't know, Venezuela probably. But the next important point-of-reference within the context of what I'm laying out here is Itapoan (also spelled Itapuã). Itapoan used to be a village quite apart from Salvador, but it has since been aborbed into the greater Salvador metropolitan area, and you fans of Brazilian music may have heard the place mentioned in the eponymous (and nonpareil) Tarde em Itapoan (Afternoon in Itapoan) by Toquinho and Vinicius de Moraes.
The beach at Itapoan starts at almost right angles to the general lay of the beaches running up the coast, then it rounds a bend and a bit further up is another lighthouse, the Farol de Itapoan. The waters off the first stretch of beach are protected by rocks and reefs and tend to be calm and good for swimming, while the waters on the far side of the lighthouse are strong, unprotected Atlantic surf. A lot of locals surf here but there are powerful currents in the waters off the lighthouse and they are only recommended for strong swimmers who know the area.
The Farol de Itapoan
(There's more to be moved to this page...!)