Culture
Thailand has an astounding amount of ethnic diversity. Learn more here
Currency
In Thailand, the currency is the Thai Baht, which is now trading at about 31 baht to 1 US dollar. The exchange rate varies regularly. Cambodia’s currency is the riel, and is trading at about 3850 riel to 1 dollar. Most Cambodian merchants prefer US dollars so it is not as big of a deal to convert your money to local currency in Cambodia. It is more important to convert your money in Thailand and vendors may not accept the dollar unless the exchange favors them.
Race
Unfortunately, racism does exist in Southeast Asia, particularly related to skin color. Lighter skin is considered a prized trait and people go to great extents to lighten their skin with products like skin creams and umbrellas to block the sun. The majority ethnic group in Thailand is the Thai people, who historically founded the Siam empire. This ethnic group is known (at least in the popular collective memory) to have lighter skin. Therefore, darker skinned ethnic groups like the hill tribes of Northern Thailand, and migrants from Burma and Cambodia, are looked down upon by some.
http://www.dpa-international.com/topic/white-better-thailand-light-skin-craze-shows-sign-fading-180603-99-560358
This prejudice for lighter skin is widely prevalent in the popular media, as you will see around Bangkok. Often, movie and television stars are only half-Thai, commonly having one European or white American parent. Sadly, racism isn’t something we can escape on the other side of the world.
Skin whitening products are growing in popularity in Cambodia and are less regulated.
In particular, the term Khmeng sre is a somewhat derogatory term that insinuates that someone is poor and from the country-side and that their skin is darker due to doing manual labor in the sun.
In Northern Thailand when we visit Chiang Rai, you are also likely to see immigrants from Burma using Thanaka face paint.
http://www.faceofmyanmar.org/thanaka/
In addition to the cool designs that some creative Burmese use, this ground tree bark is used as sunscreen and thought to lighten and soften the skin.