Google adds search suggestions to search results, generating a list of alternative search queries.

Google has added a new feature to the Google home page and other search pages. As soon as you start typing a search query, Google will open a small pull down menu directly under the search form with a list of alternative search queries based on the letters you type. The list changes as you type.

Behind each suggestion Google adds the number of search results for that particular query. Don’t put too much trust in that number, but it gives you an idea of the relative size of the amount of information available.

It is similar to the “Did you mean?” feature Google has had on the search result pages, the main difference being that Google Suggest is generated in real time.

The point is to help searchers formulate queries with more keywords — queries that are more targeted and more likely to generate relevant results. A happy searcher is, as we know, a returning searcher, and Google would love to have you back for more.

Google uses updated web search statistics to determine what queries to include. Search queries that are popular today are therefore more likely to get included. Google does not make use of your personal search history to generate the suggestions.

Google is not the first search engine to implement such a feature. Both Ask and Yahoo! have it.

Its usefulness seems to be a matter of personal taste. Some like to get to glance at the alternative search phrases and select one that is relevant. Others find the constantly changing list of queries an irritating distraction.

If you want to disable Google Suggestions, click on Preferences (to the right of the Google home page search form) and scroll down to the relevant section.

So far the feature is limited to the English language.

Google Suggest FAQ
The official Google Blog on Suggestions.