If you aren’t interested in learning how Google creates the index and the database of documents that it accesses when processing a query, skip this description. I adapted the following overview from Chris Sherman and Gary Price’s wonderful description of How Search Engines Work in Chapter 2 of The Invisible Web (CyberAge Books, 2001).
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...read all of: How Google Works

The following table lists the search operators that work with each Google search service. Click on an operator to jump to its description — or, to read about all of the operators, simply scroll down and read all of this page.

Search Service
Search Operators

Web Search
allinanchor:, allintext:, allintitle:, allinurl:, cache:, define:, filetype:, id:, inanchor:, info:, intext:, intitle:, […]

...read all of: Search Operators

You can use most of the options we discussed in Google’s Advanced Search Form in a regular search box query. If you’re a frequent searcher or a “power searcher,” this can save time because you don’t need to open the Advanced Search page and fill in various boxes; instead, you can enter the refined query […]

...read all of: Using Search Operators

Refining a query means changing or adding to the set of search terms to do a better job of returning the pages you’re seeking. Successful researchers frequently enter several queries to find what they’re seeking.
The search boxes at the top and bottom of the results page show the query for the current results page. If […]

...read all of: Refining a Query

11. Alerts
Once you’ve refined your Advanced Search, you can watch for changes in the top 20 results by setting up Google Alerts. Google will find and deliver links to new web pages once a week, once a day, or as soon as Google finds them. Simply copy and paste your advanced search query into the search […]

...read all of: Other Search Forms

When you don’t find what you’re seeking, consider specifying more precisely what you want by using Google’s Advanced Search feature. Don’t be frightened by the name “Advanced Search”; it’s easy to use, and it allows you to select or exclude pages with more precision than Google’s standard search box. Click on the Advanced Search link […]

...read all of: Advanced Search Form

This table summarizes how to use the basic search operators described in this chapter. You may include any of these operators multiple times in a query.

Notation
Find result
Example

term1 term2
with both term1 and term2
[ carry-on luggage ]

term1 OR term2 term1 | term2
with either term1 or term2 or both

[ Tahiti OR Hawaii ]
[ Tahiti | Hawaii ]

+term
with term (The + operator is typically used in front of […]

...read all of: Special Characters: Summary

Specify that results contain numbers in a range by specifying two numbers, separated by two periods, with no spaces.

For example, specify that you are searching in the price range $250 to $1000 using the number range specification $250..$1000.

[ recumbent bicycle $250..$1000 ]

Find the year the Russian Revolution took place.

[ Russian Revolution 1800..2000 ]

tags (keywords): fine tune, narrowing search, numbers, […]

...read all of: The .. Operator

Specify synonyms or alternative forms with an uppercase OR or | (vertical bar).

The OR operator, for which you may also use | (vertical bar), applies to the search terms immediately adjacent to it. The first and second examples will find pages that include either “Tahiti” or “Hawaii” or both terms, but not pages that contain […]

...read all of: The OR and | Operators

Find synonyms by preceding the term with a ~, which is known as the tilde or synonym operator.

The tilde (~) operator takes the word immediately following it and searches both for that specific word and for the word’s synonyms. It also searches for the term with alternative endings. The tilde operator works best when applied […]

...read all of: The ~ Operator