Apple doesn't tell you how to take a screenshot with your iPad, so unless you figure or find out for yourself, if you're new to the iPad, you may not even know the feature exists. Luckily, it does, and it's really easy to do!
To take a screenshot with your iPad, simply press the Home and Sleep/Wake (Power) buttons at the same time. If you nail it, the screen will flash and you'll hear the same camera shutter sound that's made when you're taking a photo.
To access and share your screenshots go to Photos and open the Camera Roll. (Note: Images updated to reflect iOS 7.)