FLAC is the highest quality format for digital audio.  It is playable on any computer operating system and can be streamed through the internet.  It's possible to store thousands of hours of FLAC audio to a single flash drive smaller than your thumb.

FLAC is an acronym for Free Lossless Audio Codec. Since FLAC is a lossless scheme, it is suitable as an archive format for owners of CDs and other media who wish to preserve their audio collections. If the original media are lost, damaged, or worn out, a FLAC copy of the audio tracks ensures that an exact duplicate of the original data can be recovered at any time. An exact restoration from a lossy copy of the same data is impossible. FLAC being lossless means it is highly suitable for transcoding without the normally associated quality loss between one lossy format and another.

The FLAC digital audio file is extremely resilient and moves across the connected world at the speed of light.  It can be copied and stored in multiple locations, further increasing it's life expectancy to what one might consider indelible.  This has lead to a worldwide boom in preservation of old memories from audio reels, audio cassettes, and one-of-a-kind vinyl recordings.  Many have even converted their CD music collections to this more usable and durable format.