If you have a Mac, then you can just press the spacebar and it will quickly show you the preview of the selected file. But this feature is not present in Windows, not even in the latest version of Windows 10. The developer of open-source QuickLook also felt this void when he thought of creating this wonderful program. QuickLook enables very fast preview of files in Windows File Explorer in the same fashion as in the Apple Mac. After installing QuickLook, you only have to select a file in Windows File Explorer and press the spacebar to see an instant preview of the selected file.
The preview will be displayed inside a small window with a push-pin button for pinning this preview on the top of other windows. It also has the default command available in the Windows File Explorer for the selected file type. For example, if you select a video file and press the spacebar, then the preview window will start playing the video and also display “Open with VLC Media Player” in the window (if you have VLC Media Player installed). You can click on this action to open the file in the default application. You can also press the Enter key to launch the associated program or execute the command.
If you want to dismiss the preview window, then you can press the Escape key on your keyboard. If you are previewing images using the QuickLook, then you can use the up-down and left-right keys to go through the various images in the folder. Similarly, you can use the mouse wheel to zoom-in or zoom-out the images. There are no special actions available for video files though.
Conclusion: QuickLook provides a quick and fast way to preview the files in Windows File Explorer just by pressing the spacebar. It can be very helpful for people who are new to Windows but have used Mac before.
You can download QuickLook from http://pooi.moe/QuickLook/.