to figure out likely alternative spellings. Google closely guards the formulas it uses to calculate relevance; they’re tweaked to improve quality and performance, and to outwit the latest devious techniques used by spammers.
Indexing the full text of the web allows Google to go beyond simply matching single search terms. Google gives more priority to pages that have search terms near each other and in the same order as the query. Google can also match multi-word phrases and sentences. Since Google indexes HTML code in addition to the text on the page, users can restrict searches on the basis of where query words appear, e.g., in the title, in the URL, in the body, and in links to the page, options offered by Google’s Advanced Search Form and Using Search Operators (Advanced Operators).
Let’s see how Google processes a query.
Copyright © 2003 Google Inc. Used with permission.
For more information on how Google works, take a look at the following articles.
- Google’s page on Google’s Technology, www.google.com/technology/.
- How does Google collect and rank results?, www.google.com/newsletter/librarian/librarian_2005_12/article1.html.
- Google’s PageRank Algorithm and How it Works, www.iprcom.com/papers/pagerank/
- Google’s PageRank Explained and How to Make the Most of It, www.webworkshop.net/pagerank.html
The results page is filled with information and links, most of which relate to your query.
- Google Logo: Click on the Google logo to go to Google’s home page.
Statistics Bar: Describes your search, includes the number of results on the current results page and an estimate of the total number of results, as well as the time your search took. For the sake of efficiency, Google estimates the number of results; it would take considerably longer to compute the exact number. This estimate is unreliable.
Every underlined term in the statistics bar is linked to its dictionary definition. Queries that are linked to just one definition are followed by a definition link.
- Tips: Sometimes Google displays a tip in a box just below the statistics bar.
Search Results: Ordered by relevance to your query, with the result that Google considers the most relevant listed first. Consequently you are likely to find what you’re seeking quickly by looking at the results in the order in which they appear. Google assesses relevance by considering over a hundred factors, including how many other pages link to the page, the positions of the search terms within the page, and the proximity of the search terms to one another.
Below are descriptions of some search-result components. These components appear in fonts of different colors on the result page to make it easier to distinguish them from one another.
- Page Title: (blue) The web page’s title, if the page has one, or its URL if the page has no title or if Google has not indexed all of the page’s content. Click on the page title (e.g., The History of the Brassiere - Mary Phelps Jacob) to display the corresponding page.
Snippets: (black) Each search result usually includes one or more short excerpts of the text that matches your query with your search terms in boldface type. Each distinct excerpt or snippet is separated by an ellipsis (…). These snippets, which appear in a black font, may provide you with
- The information you are seeking
- What you might find on the linked page
- Ideas of terms to use in your subsequent searches
When Google hasn’t crawled a page, it doesn’t include a snippet. A page might not be crawled because its publisher requested no crawling, or because the page was written in such a way that it was too difficult to crawl.
- URL of Result: (green) Web address of the search result. In the screen shot, the URL of the first result is
Size: (green) The size of the text portion of the web page. It is omitted for sites not yet indexed. In the screen shot, “5k” means that the text portion of the web page is 5 kilobytes. One kilobyte is 1,024 (210) bytes. One byte typically holds one character. In general, the average size of a word is six characters. So each 1k of text is about 1