Software To Promote and Create Web Content

Why nmap and such tools are created? I do not see a good point, because all it does is fetch the system information of the target machine. Webmasters usually know about their server and what services are running, etc. So they do not really need a program that fetch these information for them! Sounds redundant. Any idea? I would agree if you said such tools are there to spy on others people's servers... To feynm. : "It can be used to see if target ports are open on a remote machine. This was essential for me when I was setting up a server/client backup system." You did not know the open and closed ports of your machine?!

Security scanners like nmap can certainly be used to spy on other people's servers. However, a very ligitimate use of nmap is to attempt to gain access to your own server as if you were an illegitimate user. If you test your computer's security using one of these scanners, it becomes less likely that someone using that same scanner is going to find a vulnerability. Let's say you have a service running that is a potential entry point. You might not know that. So if you load up nmap, discover the hole and patch it, you just thwarted some malicious user who was running nmap for the purpose of finding that hole and exploiting it. Keep in mind that a user who is up to no good will find security scanners somehow; having nmap public is a way to provide a counterbalance to this.

nmap isn't just for figuring out what OS a remote computer is running (though it can do that), it is a general network diagnostic tool. It can be used to see if target ports are open on a remote machine. This was essential for me when I was setting up a server/client backup system. And yes, since it can be used to see what ports are open on a machine, you could potentially use it for spying.