Mostly younger people use 꿀잼. I think you aleady know what 꿀잼 means. But in case you don't know what it means, 꿀 is honey and 잼, 재미 is funny. so it means it really funny. so you can use when something is really funny. oh that is really 꿀잼. i give to you more specific example. when i saw some movie that is really funny, exciting, i can say to my Friends "the movie was really 꿀잼. 그 영화 진짜 꿀잼. and also we use 허니잼 (허니 is honey) and 존잼 (존잼 is 존* 재밌다 f***ing funny... my english is bad but i hope, my explain will be help you