Both Linux and Windows provide a GUI and a command line interface. Linux typically provides two GUIs, KDE and Gnome. Each version of Windows has a single command interpreter, but the different flavors of Windows have different interpreters. Windows users sometimes call it a DOS prompt. Linux users refer to it as a shell.
There are some companies which provides desktop/ Enterprise security products both for Windows and also Linux based software products. One such company that I came across is Comodo which provides plenty of life time free products both for Linux (Trustix Enterprise Firewall) as well as Windows (Desktop Security) based products,which protects your computer from such attacks. And also Linux based Enterprise Internet Security is the Next Generation for the computer users. You can know more about internet security surfing http://yuvi-internetsecurity.blogspot.com/.