I am using Google many years, but I still don't know what does "I'm feeling lucky" button,
and why it's placed there. Explain me .
Earlier (when the changing button and Google Instant was not there), this button directly opened up the first search result from Google.
Later, if there is no search query in the Search Bar, this button opens up the Doodles page.
Now, Google has added another Easter egg. When you hover over the "I'am Feeling Lucky" button, it changes to some other. Upon clicking it, it takes you to another page with some relation to the text. Like "I'am feeling Doodley" takes you to Doodles page.
It opens the first search result page.
Usually, Google search gives n number of results which you can click and open the URL of your wish.
I'm feeling lucky with Google Instant Disabled
Google's homepage includes a button labeled "I'm Feeling Lucky". When a user types in a search and clicks on the button the user will be taken directly to the first search result, bypassing the search engine results page. The thought is that if a user is "feeling lucky", the search engine will return the perfect match the first time without having to page through the search results.
I'm feeling lucky with Google Instant Enabled
When the user types the text and mouse over on it, it shows "I'm Feeling Lucky". By clicking on it, user will be landed directly on first search result.