Yes it's a safe thing. No, hackers can't use it from your computer. A hacker wouldn't care about a loopback adapter... if they had access to your modem or network adapter.
A loopback adapter is the same thing as a circular loop from your computer, back into your computer. A modem or network adapter would allow hackers to reach out and gain access to other computers.
Hackers want to reach into your computer and either get something, destroy something or reach out to another computer to hide their criminal activity and/or block everyone from getting to a specific computer (AKA a famous web site). Hackers would be trying to setup an impossible trace path back to them, so cops can't find them. (I have never attempted to gain access to anyone else's computer, because cops always find hackers!)
Back to the loopback adapter & how it works....
Before I became a webmaster, I used to build a DOS-based Bulletin Board System (BBS). I had 2 modems setup in my PC. To test what my callers were seeing, I would dial out on one modem (on one phone number/line) and call into my 2nd modem (on another phone number/line). Then I could see how it looked from other users point of view. All that I was doing was creating a loop from my PC to my phone company and back into my PC. I wasn't going out to the Internet, during that process.
The Loopback adapter works under the same principle. If your not connected to the Internet and you don't have a network adapter setup, you can use the loopback adapter to let Windows "think" that there is a network adapter installed on your PC. When in reality there isn't one. Then the PC calls the Loopback adapter (think phone company), then back to your PC. It doesn't go through the Internet. Hackers wouldn't care about it, because it would be a waste of their time.
If you want to, you can remove the loopback adapter. In later versions of Windows, Microsoft doesn't install it by default. If you remove it and later on want to install it manually, check out this URL. http://msdn.microsof...backAdapter.asp
For the record, the "good guy hackers", who are the paid security consultants that try to make sure corporate data is safe and secure, are called "hackers". The "bad guy hackers", who rip off passwords, credit card data, create viruses, and wreck havoc, are called "crackers". The media likes to call both of those users "hackers" by mistake. I have intentionally "made that mistake" in this reply, because until now, you didn't know the difference. Now re-read my post again, but this time substitute every instance of "hacker", with the word "cracker". Enjoy!
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