Hosts is a library for melodramatically manipulating Hosts file for various operating systems. It also functions as a program for manipulating the file via the command line.
Accessing the program with no command line arguments will display the programs help text.
If you are using Windows Vista/7 you must open cmd as an administrator. To do this, create a shortcut to cmd, then right click it and click "Run as Administrator". On earlier versions of windows, you can simply run cmd from the "Run" option in the start menu by typing cmd into the "Run" dialog box.
Open a terminal and navigate to the programs working directory. run the program with sudo to give you administrator rights. For example, "sudo hosts".