The phrase refers to the practice of downloading audio, specifically in the MP3 format, from the video-sharing platform YouTube. For example, an individual may seek to save the audio track of a music video or a lecture available on the site as an MP3 file for offline listening.
The significance of this process lies in its enabling users to access and enjoy audio content independently of an internet connection or the YouTube platform. Historically, this functionality addressed limitations in bandwidth availability and data storage, allowing for the portable consumption of content on devices with limited connectivity.