@itemize
@item 00 ... Basics: Pitches, durations, rests, clefs, keys, time sigs, ties, etc.
@item 01 ... Chords
-@item 02 ... Articulations, Ornaments, Technicals, Texts
-@item 03 ... Dynamics (single symbols, not spanners like hairpins)
-@item 04 ... Spanners (hairpins, octave shifts, trills, etc.)
+@item 02 ... MusicXML notations and articulations (articulations, ornaments, technicals, text markup)
+@item 03 ... MusicXML directions (dynamics; single symbols, not spanners like hairpins)
+@item 04 ... Spanners (hairpin, octave shift, trill, glissando, etc.)
@item 05 ... Header information (title, composer, poet, etc.)
@item 06 ... Lyrics
@item 08 ... Multiple parts (staves)
@item 14 ... Multi-staff parts (one voice on multiple staves, e.g. PianoStaff)
@item 15 ... Percussion
@item 17 ... Guitar notation: Chord names, Fretboards, Tablature notation
+@item 18 ... Figured bass
@item 19 ... Page layout: font/paper size, margins, spacing
-@item 20 ...
+@item 20 ... Compressed MusicXML files
+@item 99 ... Compatibility modes with broken MusicXML exporters (i.e. ignore beams for Sibelius 5)
@end itemize
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