What is 'fish'

This particular 'fish' has nothing to do with those animals that inhabit our lakes, rivers and oceans. It's a protocol that stands for FIles transferred over SHell and its original implementation was developed by Pavel Machek for the Midnight Commander file manager. The KDE project incorporated into their Konqueror file manager/web browser with the advent of version 3.1. So, if you're using Konqueror, you've got a powerful virtual networking tool at your fingertips.