"...but you can also save it compressed, is that the same as embedding? "

no -- file compression is a way to make files smaller and easier to move around. embedding is a way of putting your art files (photoshop, illustrator) INSIDE the layout file (InDesign, Quark) and is preferred by some people over mearly LINKING to the external art file. there are pros and cons to both, but personally i don't embed any files because then if there's something wrong with embedded image, the service bureau doesn't have a proper copy of the file to make the repair. though again, your printer is going to have a preference and you should check with them.

with fonts, you don't embed them, but you can convert them to outline, which makes them art and no longer a font. again, pros and cons -- pro: no missing fonts at the service bureau; con: you can't spellcheck art. it better be right!


"...does dot gain mean that it sorta builds on itself and clogs the image (on a micro level) so that the image is darker?"

yeah, pretty much. Dot Gain is actually caused by the paper soaking up more ink than intended, which creates a larger dot when printed. so a 10% dot will look like a 30% dot when finished. most output is adjusted for dot gain already, but again, check with your printer and see what they recommend.


"...Someone else said avoid true fonts...how do I know what kind a font is? "

what he's talking about when he says "try and avoid the use of type built in cmyk" is to not make the type a color other than black (and mainly we're talking about small point body type) for many reasons, but a few are: it's hard to control on press, the type is then made up of four screens instead of only one, it creates a lot of saturation on the newsprint and thus more dot gain and looks chunky, etc.

what "someone else" was talking about is using TrueType fonts as opposed to OpenType or Postscript fonts. unless you really want to geek-out on the intricacies of fonts, i say don't worry about it. you should be just fine with what you're doing.