The Thai currency unit is called the baht. The two best ways for acquiring baht is through and ATM and Currency Exchangers. There are 6 different colored notes and 5 coins.

• Notes: B20 green | B50 blue | B100 red | B500 purple | B1000 beige (Note: There is a B10 note too, it's brown color and not much in circulation inside Bangkok).

• Coins: 25 satang | 50 satang | B1 | B2 | B5 | B10 (Note: 100 satang = B1)
  

The most convenient way is the ATM of course. There are many banks in Thailand so you'll find many different ATM locations everywhere. Just recently, as of writing, all major bank's ATMs charge a B150 surcharge. Which is expensive already considering your own local back will most likely charge a surcharge too.

However there is one bank called Aeon that is currently fee free. You can search for their branches here at Aeon Bank ATM locations. Since Aeon is a relatively new their ATMs are not not so easy to find. Currently the most convenient ATMs can be found in MBK and Siam Discovery Center shopping malls. (Note: All ATMs in Bangkok only accept 4 digit PIN.)

Many banks also have currency exchange booths located throughout the commercial districts and tourist attractions. But you will see that their exchange rates aren't so favorable. One authorized money exchanger I recommend is called Super Rich. You'll see that they offer excellent rates. You will get better rates when exchanging larger notes; for example $100 USD note will get you better rates than exchanging $1 USD notes. One of the most convenient branch is at the Chit Lom BTS station. Head towards exit #1 and you should see the branch.

Notice that Thai notes bears the image of the beloved King Bhumibol Adulyadej. And just like anything with the King's image you should handle the money with care. For example if you drop a B10 coin on the floor by accident and it starts rolling, don't step on it. It's a major insult to the King and if a Thai person sees it they'll give you an unfriendly stare. So remember to pick it up with your hand.

You won't have a problem using credit cards in major shopping malls, restaurants and hotels. You should keep in mind though that most establishments that accept credit cards usually tack on a small service charge, about 2% - 4%.

Also most merchants will give ask if you want to pay in your local currency or exchange it into Thai baht. The conversion will cost you an extra 3% fee (which most merchants may not mention). So make sure you ask the merchant what types of fees or service charges you will incur for using a credit card before making the purchase.

Tips for services in Thailand are not mandatory unlike other countries. Though for a country where the majority of the people working in the service industry such as housekeepers earn very little, even for the big name foreign operated luxury hotels, tipping for good service is a good gesture. Even a tip of 40 Baht is much appreciated, since it is enough to buy a small meal where they live. And let's be honest, 40 Baht for a tourist is not a whole lot of money and easily manageable.

In most parts local small street side eateries to eating in larger restaurants does not require tipping but of course it is appreciated.

A ride on a taxi does not require tipping either.