My experience with Wikipedia

I recently had a go at making a couple of edits of some disingenuous statements in the "Fractional Reserve Banking" section in Wikipedia. Now maybe I need to R.T.F.M., but the F.M. of Wikipedia seems just endless... It seems that after you make an edit you are supposed to explain your changes in a single line of text... which I duly did. But in no time at all someone undid my changes giving no explanation whatsoever. Then I tried to contact him through Wikipedia so that we could perhaps resolve the disagreement between us, but I found that I was barred from doing so because I wasn't a sufficiently established user. I was stumped. So now I have just tried making one of my edits again, stating that I'd like some explanation if anyone wanted to undo it. I wanted to add as part of my explanation that anyone about to undo my change should contact me but it seemed that the space Wikipedia allowed me was not big enough for such a sentence! I'm sure I have something wrong here - if anyone would like to explain to me the error of my ways please do.