By default your Mac captures the screenshot as a PNG file.
If you would like to change the PNG to a JPG format follow the simple steps bellow:
- Open Terminal
- Write: defaults write com.apple.screencapture type jpg
- Write: killall SystemUIServer (for the changes to take effect)
Your Mac now captures the screen in jpg format.
PS: you can use a different format instead of “jpg”. Works with tiff, pdf, etc.