The Snipping Tool is a utility that comes with recent versions of Windows. You can find it in the Windows Accessories section of the Start menu. I have it pinned to the Taskbar. I've been using it for a number of years. Rather than just describing what I want, I will often grab a small screen shot and paste it into emails etc. For example, here is where to find it in Windows 10:

In order to do this, I had to use the timer delay feature. I've also added a bit of highlighting.