Use hyphens (-) primarily to avoid ambiguity:
Small business is understood. Small-business owners should be hyphenated to avoid ambiguity.
Compound modifiers that precede a noun take a hyphen: first-quarter goal, full-time job
The hyphen is usually dropped after the noun: goal in the first quarter, works full-time
According to the Associated Press Stylebook, retain the hyphen when a modifier that would be hyphenated before a noun occurs after a form of the verb to be:
Your uncle is well-known. His son is soft-spoken.
Use to avoid repeating vowels or tripling consonants: co-owners, shell-like
Exceptions: cooperate, coordinate
Part of a series on punctuation.