Audio files
Using a computer for playback is using audio files as a source.
There are many different file formats.
Something to keep in mind when selecting a media player.
The major ones (WMP, iTunes) most of all like you to use their own proprietary formats.
The major difference is lossless versus compressed.
Compressed formats like MP3 do save an impressive amount of space at the expense of losing finer details. The higher the compression, the more apparent this will be.
The reverse is also true, the higher the bit rate (less compression) the more difficult it will become to distinguish them from the lossless original.
Beside lossless there is lossless compression. This is pretty much like how WinZip works. When expanded you get exactly the same bits as the original non-compressed version.
Although a WAV and a WAV compressed to FLAC and expanded back to WAV are bit identical some claim to hear a difference.
Most of the time the audio format used is PCM in CD quality (16 bits word with a 44.100 Hz sample rate).
Recordings are often made with 24 bit words and a higher sample rate.
On a PC you can play the original recording in the original format (if your sound card allows for it). No need to down sample the original recording to comply with CD (Redbook) format anymore.
This is called high resolution.
There are various internet shops where you can buy Hi-res.