Gimbap Cheonguk, which translates as “Kimbap Heaven”, is a great way to get to know everyday Korean food, from kimbap to ramyeon, bokkeumbap to donkasu.  A chain of eateries so common that you can often see one whilst standing in the doorway of another, Kimbap Cheonguk (look for the orange sign reading '김밥천국') is delicious, dirt cheap, and probably the single best introduction to Korean food that you can find in Seoul. You'll never spend more than 5000W for a meal, but the menu is packed with favorites like kimchi jjigae (a kimchi and pork stew), kimbap (rice and goodies rolled up in dried seaweed), and donkasu (fried pork cutlet). Kimbap Cheonguk (the name means 'kimbap heaven') is everywhere, and you haven't really been to Seoul until you've eaten in one.