2 a - Google
Over the past ten years Google has come to dominate the search engine market because of its ability to return accurate and instant answers to questions. For example
Click on graphics to open searches
The exact workings of the famous Google PageRank algorithm are a trade secret and it changes constantly, but it is based on a calculation of the number of other web pages that link to a given page. It was developed at Stanford University in the 1990s by Ph.D. students Larry Page and Sergey Brin, who were in turn influenced by the citation counting technology developed by Eugene Garfield in the 1960s and which is used in the Web of Science database.
Just like a database Google works by finding terms you have entered. Although there are special "metadata" tags attached to web pages Google actually indexes the first 10,000 or so words on a page meaning that you can track down a phrase or name no matter how obscurely it is buried. Generally variant word endings are also searched and a spell check alerts you to typos!
2 b - Some special Google searches
We will be looking at Google Scholar and Google Book Search later but it is worth having a look at some of the specialised searches and services available through the more link.
Alerts allow you to be emailed as new material of interest is found by Google.
Earth requires a software download and then gives you satellite images of almost anywhere in the world.
Finance gives you business news and information.
Images allow you to search and download images from web pages.
Maps allow you to search maps and find directions.
News allows you to search stories from thousands of newspapers and other sources.
2 c - Other search engines
Google is not the only search engine in widespread use and if you wished to be sure you have searched the "whole web" you should use others as well. University of California Berkeley Library has a useful discussion of the operations and advantages of the major search engines. You can also use a meta-search engine like the unfortunately-named Dogpile or the classier Copernic or search.com. By and large, however, Google does the job and meta-search engines are not generally recommended.
For searching images the web 2.0 power of Flickr outperforms Google Images. Searching on mate selection in birds compare the Flickr results with those from Google Images.
There are other search engines like SearchNZ and Yahoo Australia & NZ and more recently Wolfram Alpha and Microsoft Bing have appeared to challenge Google's monopoly.
Wolfram Alpha is a “computational search engine” and does quite a neat job of answering the question “Where is Samoan spoken?” Read the article Stephen Wolfram: Can he topple Google? You can also check out the comparative performances of Bing and Google in an actual search.
2d – At the movies
If you know of other good ones please leave a comment.
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