I've asked a Korean-American friend to answer this question.
Although 16th birthday is not usually as special as the 18th birthday, we do still celebrate it in Korea. The legal drinking/driving age is 19. Valentines Day is usually big when the girls give the guys chocolates. Also, there is also such thing as the "White Day" when guys would give girls some sort of candy - anything from lollipops to just plain hard candy. Teens keep many anniversaries also, especially those who have girl/boyfriends (100th day and 365th day are pretty big)
And of course we celebrate Christmas. It's one of the major holidays teens celebrate.
so for your 18th birthday, you hold a party like a 16th birthday party? ..is there any traditions of some sort?
For those couples.. do you mean the 100th and 365th day they are together?
Thanks so much for your help!
Yes. 18th birthday is usully more "valued" in a sense you have more freedom. 16th birthday - not so much. It's not like you can get a license or anything like that. Teens in Korea celebrate their 18th birthdays with their friends usually at a restaurant or even karaoke room. Lots of food, presents, and a birthday song. I can't think of any obvious traditions other than that because it's very much like how we celebrate it here.
And yep! I meant 100th and 365th day they (the couples) are together.