shutter
Shutter is a free source screenshot tool with which one can take a screenshot of a particular window, area, whole screen or a website. Using this you can also edit the screenshot taken.It allows the user to add text, arrows, squares, rectangles, etc. to the screen shot, pixelize the private data, auto-increment the shape or crop the screenshots. It also provides an option to share the screenshot. It comes with a wide variety of plugins to make it more rich and efficient.