Beachwear is special clothing, which everyone may and should wear on a traditional urban beach. It is interesting that beachwear in terms of material "volume" on the body as a rule drops somewhere between what a man or a woman wears when fully clothed in swimwear. There are some rules concerning dress code in such public places as pools, where men visitors typically wear briefs of Lycra and women can be seen as a rule in one-piece of Lycra swimsuits. However, people wear something more substantial as a rule, when they are on a traditional beach, and an urban beach is especially concerned.
Men's dress code at beach may consist of beach pants, but it should be long enough to cover legs almost to the knees, and at times beyond. Men's dress code for urban beach consists of traditional beach shorts, it is very comfortable, because beach shorts look like traditional regular outerwear, but those shorts are made on the base of non-absorbent materials and that's why shorts can dry fast. Dark colors, such as gray, black, brown, blend are very comfortable for warm-weather business array, and also can quickly get dried in the sun, because light is absorbed by dark color.
Women's dress code on the beach usually consists of tank top and a pair of shorts. At present, there is a tendency that women's and men's dress code at beach is becoming more like dress code for swimming pools, and nowadays we can see men in trunks and women worn in bikini. As you probably know, swimsuits are commonly designed with the purpose to cover at least such intimate parts as genitalia. Men's dress code in swimming pools traditionally consists of shorts, Speedo-style briefs, trunks, boardshorts, thongs, cut-off jeans or jammers. Pools dress code for women is usually bikinis, thongs or one-piece swimsuits.
There is some non-traditional women's wear for beaches, for instance monokini. It is a style of women's swimsuit which usually looks like traditional beach bikini with bottom, but there is no corresponding top and that's why woman's breasts are commonly uncovered. Monokinis are rather popular in many countries around the world, especially it concerns Europe and South America, but perhaps because of particularly strongest taboos in the United States monokinis are almost never seen, but in such places where the strong European tourist influence is present. It is sometimes supposed to be more acceptable for adult girls who leaves their breast uncovered.
You can see swimsuits also on traditional urban beaches and around indoor and outdoor swimming pools even if there is no swimming. Many procurators believe that kids of both sexes should be worn in T-shirts outdoors to protect from burn caused by the sun on sunny days.
Nowadays there is a special type of swimming without a swimming suit - it is a special form of nudism. For nude swimming and sunbathing there are special nude beaches and everyone can reserve place. Skinny-dipping - it is a slang term for nude swimming. As an alternative to traditional swimming suits some people like to use their T-shirts, underpants or trousers as a make-shift swimsuit. Norms for this tend at urban beaches are less strict than at indoor and outdoor swimming pools.
So remember, where ever you decide to swim, respect the dress code and you won't have any problems in the pool or out.