There is an intense emphasis on English in the Korean education system. Unfortunately, however, this is largely limited to reading and writing, and most Korean people are quite uncomfortable actually speaking English. It's quite age-dependent, as many young Koreans often speak fairly well, while most older Koreans do not speak any English at all. In Itaewon, Hongdae, Gangnam, and around tourist attractions, however, English is very common on signs and menus and communication is often not a problem.
Tipping is not expected in almost any situation in Korea, and will generally be met with confusion if one tries.
Korea uses the same plugs as in most European countries (type C and F plugs, at 220 volts).
