OR The use of OR in your search statement permits you to broaden or increase your search results. This is important if you did not retrieve enough titles or articles. When you use OR you are not confining your search to one specific term but you are interested in any synonyms for that term. In the search example:
gun? OR firearm? you will get a larger group of hits than if you searched for only one of the terms. This is because some sources may only use the term "guns" and not "firearms." If you searched for the word "guns" by itself, you would miss any items in which the word "firearms" is used instead of "guns."