Thai - however English is widely understood and spoken in most shops and restaurants in major tourist desinations such as Koh Samui and Phuket.
The Thai Baht is the official currency which comes in demoniations between 10 - 1000. The currency coins are called 'satang' and there are 100 satang in one baht.
Credit cards are widely accepted in both Phuket and Koh Samui.
Thailand can best be described as tropical and humid for the majority of the country during most of the year. See weather Koh Samui weather and Phuket weather for further details.
There are approximately 62 million citizens of Thailand which is broken up into 80% Thai people, 10% Chinese, 3% Malay and the rest are minorities such as hill tribes.
Thailand is one of the most strongly Budhist countries in the world. Visitors should dress neatly in all religious shrines.
Standard time is 7 hours ahead of GMT. Thailand time does not operate Daylight-Saving time.
220V and 2 or 3 (flat and round) prong plugs are the most widely used.
In general, people don't drink the tap water, with bottled water being the norm.