|
NAVIGATION:
Internet Search skills
Search Engine Overview
|
![]() |
|
![]() |
|
What do search engines do?
They search the Internet, or some portion of it, generally the World Wide Web, based on keywords.
They index words they find and where they found them.
They index hundreds of millions of individual web pages.
Limitations
No one search engine captures the entire contents of the Internet
Some content can not be searched with a general search engine, such as the "invisible web" or "deep web", which requires passwords/logins/authentication.
The Internet is a fluid environment- things changes constantly. What you find today may be gone tomorrow.
How They Search and Retrieve Results
More or Less? Expanding and Restricting Your Search
Using Google, the largest and most commonly used search engine, and the subject venomous frogs let's explore different ways to expand or restrict your search.
If you typed in both words in the Google search box Google assumes you wanted documents that include both those words, as if you typed an AND between them.
venomous AND frogs
It's important to know if the search engine you use assumes you want an AND between your words. Otherwise it might be using an OR.
venomous OR frogs
TRY THIS: Type these 3 searches into Google and see how many results you get for each one. Which one returns more results or fewer results?
venomous frogs
venomous OR frogs
frogs NOT venomous
To learn more about how some common search engines use AND, OR, NOT (Boolean operators) view the charts on these two sites.
Recommended Search Engines, UC Berkeley http://www.lib.berkeley.edu/TeachingLib/Guides/Internet/SearchEngines.html
Best Search Tools Chart, InfoPeople http://www.infopeople.org/search/chart.html
Using Plus and Minus
Most search engines handle AND and NOT by letting you add a plus sign (+) directly in front of a word you want to include. This acts as the Boolean AND.
OR by adding a minus sign (-) directly in front of a word you want to exclude. This acts as the Boolean NOT.
CAUTION: Search engines may or may not recognize Boolean operators (AND, OR, NOT) or the plus and minus signs. Sometimes it is better to simply rely on their built in algorithms and see the initial results you get. And what works one day may change overnight.
Example: greyhound -bus
How Many Ways Can You Describe That Topic?
If you are looking for information about venomous frogs you might want to think of other terms to use when searching if you aren't finding what you want.
venomous ≈ poisonous
frogs ≈ amphibian
Be specific. The World Wide Web is huge. It is better to search using specific words to describe your topic rather than be too general. If your results are poor you can always expand your search by using more general or broader words.
Finding alternative search terms (to include or exclude). Words found in search results will often suggest new ways of searching your topic.
For example:
1. When searching for venomous frogs you may discover the term poison dart frogs and retry your search with that phrase.
2. When search for information about making apple pies you may need to exclude the word computers and include the word recipe.
Phrase vs. Word Searching
Typing frogs venomous or venomous frogs means you want your search to return BOTH terms on the web page(s) that is retrieved.
But typing the search in quotes "venomous frogs" means you want the page to have this exact phrase with the words in this order. This is a more precise and limiting search.
Google ignores common words like "the" "of" but if the word is essential to your search than you should try to use phrase searching.
Example: "city of trees"
Limiting your search to specific types of websites or domains.
Websites come from different sources. Knowing that source can help you evaluate the quality of the information. Look at the top level domain (TLD) in their web address/URL.
- com - commercial businesses; this is the most common TLD
- gov - U.S. government agencies
- edu - Educational institutions such as universities
- org - Organizations (mostly nonprofit)
- mil - Military
- net - Network organizations
Read more about Top Level Domains at: http://en.wikipedia.org/wiki/Top-level_domainExample: If you're searching for health information you may want to limit your search to education (edu) or government (gov) sites to be assured of high quality information. To do that you can use Google's Advanced Search page to limit your search to those sites.
Below you can see I am searching for west nile virus and limiting my search to a government website. I could also have put quotes around the phrase "west nile virus" to insure that I didn't get websites that mentioned these words individually but were not related to this illness.
NOTE: You can also limit your search to a specific website, such as microsoft.com or idaho.gov
Limit your search to specific file types
By using Google Advanced Search you can limit you search to specific types of files: [File type] - such as PDF, Microsoft Powerpoint, Word, Excel, etc.
Capitals or lower case?
Google searches are NOT case sensitive. George Washington,
GEORGE WASHINGTON, and george Washington will
produce the same results. If in doubt about the search engine you are using
type in all lower case.
Limit your search to specific languages or using the translation feature.
Use Google Advanced Search to limit search results to a specific language.
If you find a page of interest in another language you can click on "Translate this page"
Example: Search these key words official site eiffel tower
Don't use a general search engine when you need
something very specific. Although Google is excellent at offering many different
types of searches sometimes it saves time to go to a specialized search site.
General Search Tools
Our selection of search tools to try - all on one page.
http://www.boisepubliclibrary.org/Research/websearch.shtml
Looking for a multimedia file, image, sound
or video?
Search the image page on Google
http://images.google.com/ or
Yahoo images at
http://images.search.yahoo.com/images or
use one of multimedia search sites on this page:
http://www.boisepubliclibrary.org/Research/images/imagesearch.shtml
Trying to find a person or business?
Use a directory like
www.anywho.com,
www.switchboard.com
Find more directories on this page
http://www.boisepubliclibrary.org/eCollections/Websites/directories.shtml
Looking for breaking news?
Go to the News section of Google
news.google.com
or
Yahoo News news.yahoo.com/
Because anyone can post anything on the Internet
it is important that you remain critical of what you read. Here are some
key elements you should look at to ascertain if this website is provide useful
and valid information.
Purpose -What is the purpose of the web site?
Authority - Who created it and maintains it and vouches for its content?
Currency - Is the site out of date?
Objectivity/bias - Are they trying to sell you something?
Appropriateness - What audience are they writing for?
For more discussion about evaluating websites visit:
Website Evaluation Form from U.C. Berkeley tutorials
|
|
Medical and health websites - look to see if it has the HON seal, which indicates they adher to the HONcode of ethical standards. |
Look at these websites and decide if they are real or fake.
http://www.mcwhortle.com/index.htm
http://haggishunt.scotsman.com
Last Updated: 11/25/2008 grr/AS
|