The MP3 codec is one of the most popular formats, along with PDFs, HTML pages, and other strange names we’ve all heard of at least once. The news is that all patents and licenses owned by the format creators, the Fraunhofer Institute, have now expired.
It’s a historical event: it means that any program today can integrate the codec without first passing through the licenses of the Fraunhofer Institute. For example, Audacity could include it in the program itself, instead of asking to download an external plugin like LAME.
Technically, just one of three fundamental patents for MP3 is now expired, but the Fraunhofer Institute has given up its rights on all three, asserting that in the industry there are now many audio (and video) formats with better quality/compression ratio than MP3.