Transition metals are strictly defined as elements with ions having partially-filled d sub-shells, the first row from Scandium to Zinc have incomplete 3d sub-shells. Although electron shells are usually filled from the inside out (i.e. 1, 2, 3 etc in order), the 4s subshell sits at a lower energy level than the 3d, so it fills up first. Elements which can lose one or two electrons easily are usually metallic (that's pretty much what a metal is: positively charged nuclei in a cloud of loose electrons, hence the way they can conduct electricity).

Chemically this is accurate, in that you could use it for your chemistry revision. But enough of the lecture, on with the song.

Where you see a number and a letter, they should be read as number-letter (e.g. 4s is pronounced "four-ess" not "fours")