system
1
Here is a good article to read for those who have way too much security…aka overlapping security.
Keith has Norton AntiVirus, Malwarebytes' Anti-Malware, SUPERAntiSpyware, Windows Defender, and Windows Firewall. Is this overkill?
http://www.pcworld.com/article/225240/too_many_antivirus_programs.html#tk.hp_new
Norton AntiVirus and Windows Defender are both real-time antivirus programs. You should remove one of them.
??? ??? ??? Windows Defender - an antivirus? ??? ??? ???
system
3
Win Defender is a sort of antivirus.
DavidR
4
No it isn’t it is an anti-spyware application.
Windows Defender is software that helps protect your computer against pop-ups, slow performance, and security threats caused by spyware and other unwanted software
system
5
system
6
The number one anti-malware tool is the one that gets the least attention – the anti-stupid program that should reside inside that hard drive on your shoulders.
system
7
too true but a good antivirus cant hurt 
system
8
Over loading your computer with antimalware utilities and antivirus programs can bring your performance down… 
DavidR
10
Sorry, but it really doesn’t matter what you might think it is, as anti-spyware applications are different to anti-virus applications, whilst the edges are blurred, most are designed to work with AVs.
This you can see by a number of forum members signatures indication that they also have anti-spy/malware applications along with avast.