the basic difference is that one is human, the other lives at the bottom of a pond! I dont know what its like now but a tiff spends lots of time in a classroom, then gets promoted very quickly and knows not a lot but think they do. A stoker on the other hand does the minimum basic training , then goes to sea to learn the job and gets his experience that way. In the days of old a stoker was an MEM, a tiff an MEA - dont know what it is now though. Just go in with an open mind, there are only 2 options - you will love it or hate it, there is no middle ground. Also be glad there are no steam ships left - nasty stuff but interesting !! good luck.