If you want to preview files in Windows 11/10 without opening them, then you can use QuickLook, File Viewer Plus, One Commander, or Seer app.

Windows Explorer displayed .pdf files as preview thumbnails on Zill Niazi’s old Windows 7 laptop. But on a new laptop, also running Windows 7, it displays them only as icons. Can this be fixed ...

Windows Vista only: Vista's Preview Pane can be helpful in determining exactly which file you're looking to open, and PreviewConfig lets you extend its usefulness beyond the handful of files Vista ...

The Windows Explorer file management application in Windows 7 includes a preview pane that you can use to view the contents image files and other files on your hard drive.