Greenshot captures your screen and performs other operations on the resulted image while also coming with some additional useful tools. With this software you are able to capture the full screen, a selected region of it, a window or an entire webpage even if scrolling is needed. A downside is that it only works with Internet Explorer.
On the other hand, being Open Source software, it is amazing that you can use it to annotate the captured screen, highlight or obfuscate the regions you need to stand out or blur in the background.
Screenshots are easy manageable thanks to the possibility to save them to an image file, print or copy them to clipboard and share them over the internet by e-mail or social media.