I know this type of thing has been posted before, but I'd like some general things cleared up. I want to make something like this to connect an electric imp (3.3v) and an arduino uno (5v).https://www.sparkfun.com/products/8745
The BSS138 in the schematic is described as an "N-Channel Logic Level Enhancement Mode Field Effect Transistor".
I have a decent selection of components at home - some BJTs (2N3904, 2N3906), MOSFETs (IRF830), JFETs(TL071,TL074).
Why choose one over another? If there's some basics I should read, please let me know.