I know Korea has major holidays like Seollal and Chuseok, but I don't really understand what happens during?

Korean holidays follow the lunar calendar for the major ones, so dates shift each year. The most important are Seollal (Lunar New Year, late January or February) and Chuseok (Mid-Autumn Festival, September or October). Both are 3-day holidays and most businesses close.

Seollal traditions. Families travel to the eldest male relative's home for the ancestral memorial rite (차례) and to share rice cake soup (떡국), which symbolizes growing one year older. Children perform a deep bow (세배) to elders and receive money (세뱃돈) in return. Traditional games include yutnori (a board game with sticks), kite flying, and Korean wrestling.

Chuseok traditions. Originally a harvest festival. Families gather to prepare and eat songpyeon (half-moon rice cakes), visit ancestral graves for vegetation clearing (벌초), and perform rites with new harvest grains and fruits. Tens of millions of people travel during these holidays, creating Korea's largest migration each year.

Other holidays. Children's Day (May 5), Buddha's Birthday (April or May, lunar), Liberation Day (August 15), Constitution Day (July 17, observed only), National Foundation Day (October 3), Hangeul Day (October 9), and Christmas (December 25) are also public holidays.

What it means for you. Public transit is busy and expensive on travel days. Many small businesses close for 3 to 4 days during Seollal and Chuseok. Major shopping malls and convenience stores stay open. Foreigners are often invited by Korean coworkers or friends to share holiday meals, which is a great chance to experience family culture firsthand.