Windows comes pre-equipped with the Snipping Tool, a lightweight utility designed to snap and share basic screenshots. While there are other third-party screenshot applications (we've recommended MonoSnap in the past) offer some extra features or usability, the Snipping tool is still a useful application when you just want a basic screenshot, without any bells and whistles. To launch the Snipping Tool, hit the Windows key on your keyboard and type "Snipping Tool" (you can also find it under 'Windows Accessories').
The Snipping Tool interface is small and simple. To 'snip' a portion of your screen, just click New and you'll be offered a crosshair cursor to click-and-drag the portion of your screen that you'd like to capture. You can also choose a full-screen shot, and it has the helpful addition of building in a delay (useful for capturing menus or highlighted text).
One unique feature of the snipping tool is that allows you to do a free-form screen capture, rather than just dragging out a rectangle, like this example:
You can do this by clicking on the drop-down menu next to "New" and choose "Free-form snip":
Once you've captured your screenshot, you'll get an option to make some basic edits before saving and sending it.