for some reason your last variation on the equivalent code was easier for me to understand :
var str = manifest.a.filename + '\n' + manifest.a.aphorism + '\n' + manifest.a.dog;
and i think i get it now. the alert itself is executing JS (\'n') as it reads the value. and so, the alert has 3 lines.
as far as why don't i try watching a basic JS course on youtube, that makes me smile. i have downloaded and gone thru the JS courses and lessons from : the new boston, adam khoury, stephan mischook, derek banas, code academy, jream, tutor4u, some of w3schools sections, some parts of developer.mozilla, and 2 or 3 others that i don't remember because i recently deleted them for space. i have made DVD's of several series and watched them over and over (even played them while sleeping in hopes of absorption). and not just watched them, watched them on one screen and wrote and tested the code on another screen in notepad++ as i went along. but even having done all that, i don't blame you for thinking i am brand new at this. i am old at studying the subject, but a dunce at actually learning it.
however, those lessons (and 1 or 2 brilliant (to me anyway) tips from this forum months ago) have been enough for me to set up a working website, which uses a fair amount of JS, that i am proud of.
the reason i posted the question about terminology (Object, key, property, value) is that, the most ingenious part of my site, the part that was given to me here by xelawho in january, is the ONLY part i don't understand and didn't write myself. and i am beginning to believe that that tip is really at the center of what JS is all about, and i want to know it.
well, that was a lot of yakking wasn't it ?