Fair use is usually a short excerpt and almost always attributed. (One should not use more of the work than is necessary to make the commentary.) It should not harm the commercial value of the work — in the sense of people no longer needing to buy it (which is another reason why reproduction of the entire work is a problem.)
Note that most inclusion of text in Usenet followups is for commentary and reply, and it doesn't damage the commercial value of the original posting (if it has any) and as such it is fair use. Fair use isn't an exact doctrine, either. The court decides if the right to comment overrides the copyright on an individual basis in each case. There have been cases that go beyond the bounds of what I say above, but in general they don't apply to the typical net misclaim of fair use.
The "fair use" concept varies from country to country, and has different names (such as "fair dealing" in Canada) and other limitations outside the USA.
Facts and ideas can't be copyrighted, but their expression and structure can. You can always write the facts in your own words.
See the DMCA alert for recent changes in the law.
5) "If you don't defend your copyright you lose it." — "Somebody has that name copyrighted!"
False. Copyright is effectively never lost these days, unless explicitly given away. You also can't "copyright a name" or anything short like that, such as almost all titles. You may be thinking of trade marks, which apply to names, and can be weakened or lost if not defended.
You generally trademark terms by using them to refer to your brand of a generic type of product or service. Like an "Apple" computer. Apple Computer "owns" that word applied to computers, even though it is also an ordinary word. Apple Records owns it when applied to music. Neither owns the word on its own, only in context, and owning a mark doesn't mean complete control — see a more detailed treatise on this law for details.
You can't use somebody else's trademark in a way that would steal the value of the mark, or in a way that might make people confuse you with the real owner of the mark, or which might allow you to profit from the mark's good name. For example, if I were giving advice on music videos, I would be very wary of trying to label my works with a name like "mtv." :-) You can use marks to critcise or parody the holder, as long as it's clear you aren't the holder.
Article comments
1 - Tom Johnson
Dew, for some really interesting reading about copyrights, check out John Oswald and Plunderphonics. He created music from other artists work but did so in a way that only accentuated the gifts that made these songs so popular in the first place. He got his butt sued off by a number of record labels and essentially went into hiding with the aid of Negativland and their record label Seeland. What makes this so interesting is that he is doing something that, essentially, celebrates the music the artists made in the first place. He makes no attempt to disguise his sources, but the end product is so artistic and meaningful, not to mention often humorous, that it's hard to believe a band would get upset about it. Maybe they didn't, but their labels sure did. This could put an interesting spin on your work.