English uses at least two types of dashes (en dash and em dash) along with hyphens, and there are (fairly complex, in my opinion) rules on when and how each should be used. What types of dashes or hyphens appear in Spanish? What are the rules governing their usage?
The Spanish names for the hyphen, en-dash and em-dash are guión, semiraya o raya menor, and raya, respectively. In Spanish, the en-dash is not widely used although, due to English influence, its use has become rather common nowadays.
The raya (em-dash) usually indicates separation; for example, it signals interventions of different characters in a dialogue and it also can be used to signal a new item in a list. The raya is also used to avoid repeating a word or a group of words.
On the other hand, the guión (hyphen) usually indicates union: of two words as in científico-técnico, of suffixes and words, as in intra-aórtico, and it is also used, as the hyphen, at the end of a line to indicate that a word will continue in the next line. The guión is also used between numbers forming an interval, as in pág. 178-185.
The following image shows a comparison of the three signs as produced by LaTeX using the palatino font at a font size of 80pt (the letters were included only to show the position of the symbols with respect to the text baseline):