Cygwin is a Unix-like environment and command-line interface for Microsoft Windows. Cygwin provides native integration of Windows-based applications, data, and other system resources with applications, software tools, and data of the Unix-like environment. More info »
Use with mintty (available off the install) and you've essentially got PuTTY + cygwin. Fantastic.
Great! Lets you practice on you Linux commands while in a windows environment. It can take a little getting used to due to some compatibility issues between Unix naming conventions and window's. But it still works great!
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