Z:gnu-www-ja-why-audio-format-matters--246e9b-Unfortunately, that is not the/en

Unfortunately, that is not the world we live in. MP3 is a patented format. What this means is that various companies have government-granted monopolies over certain aspects of the MP3 standard, such that whenever someone creates or listens to an MP3 file, even with software not written by one of those companies, the companies have the right to decide whether or not to permit that use of MP3. Typically what they do is demand money, of course. But the terms are entirely up to them: they can forbid you from using MP3 at all, if they want. If you've been using MP3 files and didn't know about this situation, then either a) someone else, usually a software maker, has been paying the royalties for you, or b) you've been unknowingly infringing on patents, and in theory could be sued for it.