When using the Boolean operator NOT, you DO NOT allow the computer to locate documents that contain the word typed after it. In other words, it ignores all the pages that contain the word you type after the operator NOT. Think of it this way: IF I want to find Web sites on all sports, but NOT on golf because I don't like golf, THEN I will type this in the search box: sports NOT golf. (It is best to capitalize Boolean operators because some search engines require it.)

sports NOT golf

is the same as typing

+sports -golf

(You need to put one space before and after the word NOT. There's no space after the + and -, but there is a space between the +sports and the -golf.)

What about combining AND with NOT? Picture a yummy ice cream sundae. You like bananas and fudge on your ice cream sundae, but you're allergic to nuts.

banana AND fudge NOT nut

* Notice the singular form of the keywords were used. Usually, it is best not to search for the plural of a word. If you want information on scooters, and type the plural form (scooters) in the search box, you will miss all those pages that have scooter (the singular form) on them.

Turn on Rockwell Schrock's Boolean Machine to better understand the concept of using NOT. Roll your cursor over AND, OR, and NOT and watch what happens to the picture.

Let's try this search with NC WiseOwl. Quick tip: Print these directions before you link to the site.

(If you are asked for a password, type: wiseowl.)

1. Click ENCYCLOPEDIAS on the NC WiseOwl home page.
2. Click the OPEN button underneath Grolier Multimedia Encyclopedia.
3. Find the search box, and then click on the button labeled ADVANCED. You're going to do an advanced search using Boolean logic!
4. Make sure FULL TEXT SEARCH is selected. You want to search through entire articles, not the "article titles only."
5. You will learn in 8th grade that oceans contain over 97 percent of all the water on our planet, and that underground water makes up less than 1 percent. The remaining 2 percent of water is frozen in glaciers and ice caps.
6. Let's imagine that you want to study groundwater that occurs naturally, but you don't want additional information on wells and drilling. So, you decide to do a search on groundwater NOT wells.
7. Type groundwater in the first large search box.
8. Select NOT from the little drop menu, instead of AND.
9. Type wells in the search box to the right of NOT.
10. Click GO.
11. How many "hits" did you get? _____
12. Do a search again, but this time only type groundwater in the search box and click GO! (Don't make any other changes like you did earlier.)
13. How many "hits" did you get? More than before, right?!