Seoul is not only the capital of South Korea, but also its largest city. With roughly 10 million people in Seoul and another 25 million in the surrounding metro area, there are a lot of people trying to get from point A to point B. Thankfully, Seoul has many options to get you anywhere you want to go. Walking or biking short distances is great, but for those farther destinations, Seoul has a great public transportation system that is cheap, easy to use and dependable.
Although many people choose to drive themselves to their destination, Seoul doesn't have the best reputation for traffic and safety. It's much easier and cheaper for people to use public transportation. The most popular of these is the subway system. It is the simplest and cheapest option to get you to the majority of places you need to be. Running from 5:30 am to midnight every day, the trains are dependable, clean and safe.
Coming from a small town in Illinois, I was used to driving everywhere I needed to go. I have only used public transportation a handful of times while visiting other cities so this was pretty scary and overwhelming at first. However, it really was very easy to understand, and now I love it!