In the United States, making a copy without permission is generally going to be a copyright violation, unless the copying is a fair use. Fair-use defenses look at four questions, and the answers to the questions can tip the scales in favor of or against a finding of fair use:
- Does your kind of copying affect the market for the original? To what extent can your copy fulfill the demand for the original? What if there were widespread copying of the kind you're considering? The more potential there is for the copies to replace the original, the less likely it is to be fair use. (This is the most important factor in the analysis.)
- Why did you make the copy? If you made the copy for purposes of news reporting, criticism, or commentary, it's more likely to be fair use. If you made a copy just so you could emjoy the work again whenever you felt like it, that may still be fair use, but it is somewhat less likely. If you made a copy just so you could sell it for profit, that's almost certainly not fair use.
- How much did you copy? Did you copy the whole thing, or did you copy only as much as you needed to achieve your purpose under Question 2? If you copy "too much" – either in the raw amount or as a fraction of the whole work – it's less likely to be fair use.
- What did you copy? Highly creative works, such as poems, music, and movies, are at the "core" of copyright principles. A fair use analysis will be more stringent in these cases than when dealing with a copy of a purely factual work, such as a phone book, biography, or list of statistics. Such works are still protected by copyright, but that protection is not as strong.
So take all of those and imagine the answer to each on a spectrum. If you see things generally tipping in the direction of fair use, that's a good indication that you're going to be safe. If you see things tipping in the other direction, you may want to reconsider.
These questions can be trickier than you might think. If you're dealing with a real situation, you should consult an attorney to get an answer specific to your situation.
But what if I don't make any money?
This fact tips the scales in your favor, but only on Question 2; you still need to consider the other factors. Whether you make money is less important than whether your copying deprives the copyright owner of the opportunity to make money, but then you have to balance that consideration against the First Amendment principles embedded in fair-use analysis.
So if you're ripping Star Wars DVDs to hand them out as Christmas presents, your lack of a profit motive will not save you. But a freelance broadcast journalist who includes short snippets of "Kick Out The Jams" and "Whip It" in a piece on this year's Rock & Roll Hall of Fame nominations would probably be fine, even though she's planning to make some money off her piece.