Communication and Internet
If your mobile phone is working on GSM networks only, it won't work in Korea. You can rent a mobile phone at international airports. Despite the explosive use of cellulars phones, public phones are still available in many places. Many public phones (still) take coins. There is only one type of public phonecard that works on all public phones (hurray for Korea!).
Access to the internet is a widespread commodity in Korea, almost everywhere you can have access to wireless internet, but not always without having a subscription to a mobile phone company. But you will find internet caf? even in villages in the countryside and in many cases they are open for 24 hours a day. Such a place is called "PC bang", typically it cost you 0.70 Euro (US$ 0.90) per hour. To recognize a PC bang is easy: "PC" is always signposted in English.
There are ATM machines everywhere, but only very few accept a foreign bank card or foreign credit card! Apart from some well known tourist centres you will only be able to get money out of an ATM in the larger cities and then only with the larger banks such as the Korea Exchange Bank. Then still you will only be successfull if the ATM is marked with "Global Access" or "Foreign cards accepted". From the several available ATM machines, one or two are marked as such. Changing money is not a problem with larger banks. Be aware that you can use your foreign credit card for paying only in a very limited number of places, like in international hotels and on airports. Without a Korean bank card, be sure to have enough cash with you, especially in the countryside.