The hyphen (‐) is a punctuation mark used to join words and to separate syllables of a single word. The use of hyphens is called hyphenation.
The hyphen should not be confused with dashes (‒, –, —, ―), which are longer and have different uses, or with the minus sign (−) which is also longer.
Hyphens are mostly used to break single words into parts, or to join ordinarily separate words into single words. Spaces should not be placed between a hyphen and either of the words it connects except when using a suspended or "hanging" hyphen (e.g. nineteenth- and twentieth-century writers).