Screenshot capturing let Mac users capture anything displayed on their screen and save as image files. Mac OS X system has the power to save anything on your screen without any third party screen capture apps. What you need is just to press the Mac screenshot keys combination and screenshots will be saved as .png files on your desktop automatically.
Note that if you want to save a frame of certain video on Mac, you can refer to this guide to take a snapshot of video on Mac.
The new method to capture and record on Mac
Since Mac OS 10.14 Mojave, the new screen capture utility was added. Now you can press Command-Shift-5 on your keyboard and start capture screen as images or record screen videos from the onscreen control bar. Refer to this guide to record screen videos on Mac for more details.
How to take a screenshot on Mac?
The quickest way to capture your Mac screen is to hold down the Command, Shift and press 3 keys at the same time. This will take a screen shot of your entire screen on Mac and save the screenshot to your desktop as a PNG file.
Take a screenshot of part of Mac screen
If you do not want to capture the whole screen on Mac, press the Command, Shift and 4 keys at the same time on your Mac keyboard, Mac OS X turns the cursor into a crosshair pointer you can use to select whatever part of your display. Move the crosshair pointer to where you want to start the screenshot and drag to select an area on your Mac screen, release your mouse to finish capturing screenshot on Mac and find the screenshot file in PNG format on your desktop.
Taking screenshot of a window on Mac
You can press Command-Shift-4 on your keyboard, the pointer changes to a crosshair, then hit the Space bar on your keyboard, the pointer changes to a camera. Move the camera pointer over a window to highlight it and then click your mouse or trackpad to take a screenshot of a window on Mac. You will also be able to take a screen shot of the Dock, the entire menu bar, a single open menu, the desktop, or any open window following the same way.
Browser windows are always too small to display the whole web page without scrolling. Thus you can’t capture the entire web page using the shortcuts above. Check out this tutorial to capture full web page screenshots on Mac using Firefox.
Update May 2018: this article was originally published in Mar 2016. In this update, we edited the window capture method on Mac.
Update Aug 2018: Mac full webpage screenshot added.
Update Nov 2018: added the new method to take screenshots for Mac OS 10.14 Mojave and later.