The Body & Social Conventions
The Western liberalism embraced by the Thai sex industry is very unrepresentative of the majority Thai attitude to the body. Clothing – or the lack of it – is what bothers Thais most about tourist behaviour. As mentioned above, you need to dress modestly when entering temples, but the same also applies to other important buildings and all public places. Stuffy and sweaty as it sounds, you should keep short shorts and vests for the real tourist resorts, and be especially diligent about covering up and, for women, wearing bras in rural areas. Baring your flesh on beaches is very much a Western practice: when Thais go swimming they often do so fully clothed, and they find topless and nude bathing extremely unpalatable.
According to ancient Hindu belief, the head is the most sacred part of the body and the feet are the most unclean. This belief, imported into Thailand, means that it's very rude to touch another person's head or to point your feet either at a human being or at a sacred image – when sitting on a temple floor, for example, you should tuck your legs beneath you rather than stretch them out towards the Buddha. These hierarchies also forbid people from wearing shoes (which are even more unclean than feet) inside temples and most private homes, and – by extension – Thais take offence when they see someone sitting on the "head", or prow, of a boat. Putting your feet up on a table, a chair or a pillow is also considered very uncouth, and Thais will always take their shoes off if they need to stand on a train or bus seat to get to the luggage rack, for example. On a more practical note, the left hand is used for washing after defecating, so Thais never use it to put food in their mouth, pass things or shake hands – as a foreigner though, you'll be assumed to have different customs, so left-handers shouldn't worry unduly.
Thais very rarely shake hands, instead using the wai to greet and say goodbye and to acknowledge respect, gratitude or apology. A prayer-like gesture made with raised hands, the wai changes according to the relative status of the two people involved: Thais can instantaneously assess which wai to use, but as a foreigner your safest bet is to go for the "stranger's" wai, which requires that your hands be raised close to your chest and your fingertips placed just below your chin. If someone makes a wai at you, you should generally wai back, but it's safer not to initiate.
Public displays of physical affection in Thailand are more common between friends of the same sex than between lovers, whether hetero or homosexual. Holding hands and hugging is as common among male friends as with females, so if you're caressed by a Thai acquaintance of the same sex, don't assume you're being propositioned.
Finally, there are three specifically Thai concepts you're bound to come across, which may help you comprehend a sometimes laissez-faire attitude to delayed buses and other inconveniences. The first, jai yen, translates literally as "cool heart" and is something everyone tries to maintain – most Thais hate raised voices, visible irritation and confrontations of any kind, so losing one's cool can have a much more inflammatory effect than in more combative cultures. Related to this is the oft-quoted response to a difficulty, mai pen rai – "never mind", "no problem" or "it can't be helped" – the verbal equivalent of an open-handed shoulder shrug, which has its basis in the Buddhist notion of karma (see "Religion"). And then there's sanuk, the wide-reaching philosophy of "fun", which, crass as it sounds, Thais do their best to inject into any situation, even work. Hence the crowds of inebriated Thais who congregate at waterfalls and other beauty spots on public holidays (travelling solo is definitely not sanuk), the inability to do almost anything without high-volume musical accompaniment, and Songkrahn, Thai new year that lasts a minimum of three days involving all in the national waterfight which takes place every April on streets right across Thailand.