About hyphens

Question

What is a hyphen? –Juan 

Answer

A hyphen is a punctuation mark. In written English, hypens are used to connect words, parts of words, and numbers.  Specific examples of these uses are shown below. 

To create compound words

• This is not a cost-effective approach for solving our healthcare crisis. 
• The newly discovered planetary system is 42 light-years away. 
• Do you have an up-to-date list of our office staff? 
• There was a lot of anti-American feeling when the war began.
• My mother-in-law only speaks Italian. 

To indicate a range of numbers or period of time

• Read the article on pages 112-15. 
• Kofi Annan served as Secretary-General from 1997-2006. 
• The college will be closed for vacation from December 20-January 12.  

To mean “to” 

• The New York–Los Angeles flight takes about 6 hours. 
• At the football game, Amherst beat Williams, 23-20.

Email addresses and websites

Hyphens are also used in email and web addresses. For example, the web address for Merriam-Webster's Collegiate Dictionary site is: 

merriam-webster.com

I hope this helps.