lucy24 - 9:44 pm on Mar 21, 2013 (gmt 0)
It's not a recording as such, no. You could think of it as a highly specialized synthesizer. That's why midi files are measured in kilobytes rather than megabytes.
The .midi format is unsurpassed for packing a lot of information into a tiny amount of space: f'rinstance "Three Blind Mice" as a three-part round weighs in at 1.6K, while all the music accompanying a ten-page article totals 30K. That's only the melody of course-- in instrument of your choice --not the singing. Closest you can get is "Choir oohs" or possibly "Choir ahhs". (All my midis originated with lilypond, which is the musical equivalent of a command-line interface.)
It was a nasty shock to discover that the iPad's Safari doesn't play midis, whether embedded or as freestanding files. I thought all browsers did.
The question remains: What do Search and Preview do with them? Sound files they can't play, fonts they don't use...