Thailand's currency is 'Baht' (THB - Thai Baht).
It consists of several Banknotes & Coins.
As you see from the above picute,
there are banknotes as 20B (green color), 50B(blue), 100B(red), 500B(violet), 1,000B(light brown),
and coins as 10B (inside gold color), 5B(nonagon-shaped), 2B and 1B.
also there is a unit called satang which is 1/100 of 1B.
In the front side of all banknotes, there is effigy of King Rama IV, current king of Thailand.
If you change 100 USD at banks, then you can get around 3,200 THB.
(100 USD = 32.1 THB)
You may confuse how much is the banknote because you're unfamiliar at first time.
In the left-lower side, the number is written in Thai language but they looks almost same.
Please see the number in the right-upper area of front page (which is written in Arabic nemerals).
Enjoy your holiday in Thailnad ~