Some typical food items:

• kimchi: pickled spicy cabbage (served with every meal)
• banchan: side dishes that accompany meals (inc. in price; excludes the soup, kimchi and sauces)
• bibimbap: rice (bap) bowl with colourful veggies, meat (or seafood) and egg on top (can be ordered without meat/seafood)
• dolsot bibimbap: bibimbap served in a stone hotpot (keeps the food warm longer, and you get some crispy rice at the bottom)
• gochujang: spicy red pepper paste
• galbi: beef ribs (I didn’t eat any, but including for semi-completeness)
• bulgogi: thin slices of beef (or pork)
• samgyeopsal: streaky pork belly
• jjigae: like a stew, usually orange-coloured and served in a stone hotpot
• jeon: savoury wheat pancakes
• bindaetteok: savoury mung bean pancakes (heavier than jeon)

Notes:

• Meals usually include kimchi, soup and several banchan (how many of the latter depends on how fancy the resto is)
• Taxes are included in the prices (or there are no taxes?)
• Tipping is not expected (and would be insulting), though apparently some high end restos add a service charge
• Water is served free (it was always safe in Seoul) or is available self-serve from a water filter machine; sometimes tea is served
• Chopsticks are usually stainless steel (and rectangular at the narrow end, instead of round, which also helps grip food a little)
• It’s hard to get truly vegetarian meals (except at Buddhist temples/restos) as most meals include some kind of meat, and even kimchi is often made with fish sauce

Here are a few photos of food and meals I had around Seoul (I pretty much enjoyed all of them!):