Zenmap: Nmap offical GUI
Who hasn’t heard of Nmap the open source network scanner of choice for many IT professionals, there is a reason why its so popular and some cases mandate it. By Nmap nature is a command line scanner which means users are required to learn a few things before using it. 
Meet Zenmap or the official GUI for the Nmap project. Zenmap harness the power of Nmap and options known to its users and presents it all in a intuitive and straight forward presentation. 
Zenmap is not a dumbed down version of Nmap, while, a pre-configured number of scan or profiles are included with Zenmap the user still has the ability to view and change how the scan is to be performed thanks to the Command Creator. Take advantage of Nmap without having to stress over the command line, it cannot get any easier.
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nmap, security, zenmap — May 21, 2010