Yahoo! recently introduced a new feature called Yahoo! Instant Search that makes web search a one-click process. Powered by AJAX, Yahoo! Instant Search shows the most relevant result instantly as you type your query in the search box.

If you want to jump to the Instant Search result, hit Ctrl-Enter otherwise press Enter or the click the Search button to perform a normal web search.

Here are a few screenshots of Yahoo! Instant search results for different types of queries. As you notice, Yahoo! automatically finds the contexts of the query and displays the required results. For example, a search for Stock Symbol shows the results from Yahoo! Finance website

Search for Stock (like GOOG)


Search for Sports


Search For City Weather


Search for Google


Search for Iraq shows News


Yahoo! Instant Search Vs Google Suggest
Though both use AJAX to instantly display results, Yahoo shows only the top results while Google Suggest displays related search terms and the number of expected results. Both are different features.

Yahoo Instant Search vs Google I'm Feeling Lucky
Google I'm feeling lucky search takes you to the top result on Google Web Search without considering the nature and type of the user query. Yahoo Instant Search can be considered as an advanced version of Google Feeling Lucky. And it doesn't take you the result page but displays the result in a result bubble. User has the option to search the web or visit the result suggested by Yahoo! Instant Search.

Visit Here: instant.search.yahoo.com

Source: Yahoo Shortcuts | Yahoo! Search Blog