The only official language here is Korean. However, many places will have English names and restaurants tend to have an English menu option. I would say it’s important to know even a little bit of Korean, since many older people don’t know as much English as the newer generations and really appreciate foreigners putting the effort into learning their language. Even simple phrases like 안녕하세요 (Hello) and 감사합니다 (Thank you) make a huge difference.
The currency used here is South Korean Won (₩ or KRW). It is important to note that this is different from North Korean Won (KPW). Cash is not really used in Seoul anymore. ₩1,500 is around $1. There are ₩100 and ₩500 coins and bills that range from ₩1,000 to ₩50,000. Most places like stores, public transportation, and restaurants, will prefer or only accept card payments. However, it is necessary to carry some cash in case you buy from some small traditional stores. In my case as an international student without a Korean bank account I use cash to pay for small school activities and excursions.
