We search for images in Google. It takes time to choose what we want-right? Most of the times we want a specific image under a particular category that includes people, places, plant and animal.
There is no way you can search for the images of these in Google images.
http://ookaboo.com/ is a website that has arranged images under various categories. This makes it easy for us to to search for images that we want.
In addition, all the images that you see in http://ookaboo.com/ are free for use in blogs and websites as they are placed under public domain or Creative Commons.
How this image search engine works:
This image search engine employs the Semantic Indexing technology to categorize the search results.
At present it has over 505,000 images in its database.
Here is a male Humming bird that I searched for and got: