Quick Look provides a shortcut for viewing pictures (and other content) on Macs.
Information in this article applies to Mac OS 10.8 Mountain Lion and later.
Double-click a folder of pictures or useFinderto locate and initiate the folder of pictures you want to view.

The pictures can be in any kind of mediahard disk, CD,flash drive, or memory card.
choose the pictures you want to see.
If you want the whole folder, use the keyboard shortcutCommand+Ato select all the files.

PressOption+Spacebarto kick off the first image in full-screen mode.
Quick View launches a slideshow of the chosen images automatically.
A slideshow doesn’t launch in Window view.

Still, some options are not available unless you are in full-screen mode.
Index Sheet in Quick Look
Not interested in slowly scanning the images via a slideshow?
Tap any photo in Index View to go to it in Quick Look.

To exit Quick View, pressESCon the keyboard or clickCloseon the image control bar.
Beyond Photos
Quick Look doesn’t only work with images.
It can be used with a folder containing documents and other media such as video.

Remember to kick off the folder and opt for files inside before pressingOption+Spacebar.

