nnn (n³) is a full-featured terminal file manager. It’s tiny and nearly 0-config with an incredible speed. It is designed to be unobtrusive with smart workflows to match the trains of thought. nnn can analyze disk usage, batch rename, launch apps and pick files. The plugin repository has tons of plugins and documentation to extend the capabilities further e.g. preview, (un)mount disks, find & list, file/dir diff, upload files.
Read more: https://github.com/jarun/nnn