|INFO(5)||File Formats Manual||INFO(5)|
Info files are usually created from texinfo(5) sources by makeinfo(1), but can be created from scratch if so desired.
For a full description of the Texinfo language and associated tools, please see the Texinfo manual (written in Texinfo itself). Most likely, running this command from your shell:
info texinfoor this key sequence from inside Emacs:
M-x info RET m texinfo RETwill get you there.