This is the latest in our series of articles highlighting essential system tools. These are small, indispensable utilities, useful for system administrators as well as regular users of Linux based systems. The series examines both graphical and text based open source utilities. For this article, we'll look at Krusader, a free and open source graphical file manager. Krusader is an advanced, twin-panel (commander-style) file manager designed for KDE Plasma. Krusader also runs on other popular Linux desktop environments such as GNOME.