@hyphenation: Helping TeX Hyphenate
Although TeX’s hyphenation algorithm is generally pretty good, it does miss useful hyphenation points from time to time. (Or, far more rarely, insert an incorrect hyphenation.) So, for documents with an unusual vocabulary or when fine-tuning for a printed edition, you may wish to help TeX out. Texinfo supports two commands for this:
Insert a discretionary hyphen, i.e., a place where TeX can (but does
not have to) hyphenate. This is especially useful when you notice an
overfull hbox is due to TeX missing a hyphenation (see Overfull hboxes). TeX will not insert any hyphenation points itself into a
Tell TeX how to hyphenate hy-phen-a-ted words. As shown, you put a ‘-’ at each hyphenation point. For example:
TeX only uses the specified hyphenation points when the words match exactly, so give all necessary variants, such as plurals.
Info, HTML, and other non-TeX output is not hyphenated, so none of these commands have any effect there.