The Gregowiki is a central location for all Gregorio users to find:
Gregorio is an open-source project offering software tools for typesetting (engraving) Gregorian chant scores. In particular, Gregorio is an add-on package for the typesetting system LaTeX, so it requires an installation of TeXLive.
Gregorio and LaTeX together produce PDF output suitable for printing.
The input to Gregorio is a notation called GABC, which combines the syllables of a chant text with a simple notation indicating the position and shape of each note.
For most users, it's not necessary to install Gregorio on your own computer. Instead you can access it using one of the on-line Gregorio web interfaces listed below.
gprocesswhich is a
perlscript designed to instantly show the result of a gabc file using your system's pdf viewer.
grely.rbwhich converts gabc to simple lilypond. Currently the conversion is possible only to modern notation, with great information loss.
Several published books and smaller works have been produced using Gregorio.