Grammatically Correct: The writer's essential guide to punctuation ...

Hyphen(-)
This section looks at the hyphen as a mark of punctuation, as opposed
to a component of spelling. The distinction is that in its punctuation
role the hyphen is not an inherent part of a word or phrase, but rather
is required only when words are presented in particular combinations
or ways. (For a discussion of its spelling role, turn to page 23.)
The functions of the hyphen as a punctuation mark are the
following:
• Indicating word breaks at the end of a line
• Drawing together words that form a compound adjective
• Acting as a "stand-in" for a repeated word
• Indicating special intonations or pronunciations
INDICATING END-OF-LINE WORD BREAKS
During a late election Lord
Roehampton strained a vocal chord
From shouting, very loud and high,
To lots and lots of people why
The budget in his own opin-
-Ion should not be allowed to win.
HILAIRE BELLoc, Selected Cautionary Verses
Knowing where to break a word that's too long to fit on a line
was more of an issue in the days of typewriters. (Remember them?)
Nowadays, it's a rare word processor that won't automatically do
the breaking for you. Still, it doesn't hurt for writers to have at
least an awareness of the rules: As any newspaper reader knows, a
computer's idea of word breaks can be hilarious-or worse.
125