I just found this out minutes ago and had to write about it. I never knew it was this easy to do a screenshot in OS X.
Command-Shift-3 (full screen)
Command-Shift-4 (selection)
Instantly on my desktop, a PNG image shows up with the screenshot.
I love Macs.
More OS X shortcuts [Apple.com]
Someone told me about that very early on, when they saw all my screenshots had been taken with Grab
.
Here’s another tip though – press Command+Shift+4, and then press the spacebar – you can now take a screenshot of a particular window
.