What about 어서 오십시오? <- I think I heard that one on the KTX (high speed bullet train) or maybe on the pre-flight announcements on an airplane. I have also heard something along the lines of "assossayo!" every time when I walk into a bakery, convenience store, etc. This was in Busan, though. What's the difference between "환영합니다" and this "assossayo!" that I heard all the time?