Most students use Google’s image search but have rarely seen the advanced features of the engine. The advanced search option, which appears to the right of the search bar, lets you limit your search to line drawings, faces, specific colours, size, file type and more.
One example where you could use this feature is if you were looking for an outline of a country. By limiting your search to line drawings, you could very quickly find relevant maps without trawling through every other kind of image.
Google images also lets you drag and drop images from your desk top or other website into the search bar and gives you results for similar images. Google has a video you can watch demonstrating this feature.