Toolkit allowing a user to make malware by simply choosing its features. This kind of tool does not require a considerable knowledge of programming and is easy to use. Some constructors let users make some quite complex viruses and then allow them to add a polymorphic engine to the viruses. If, say, a particular user created about 15,000 viruses with a constructor and then transmitted them to anti-virus companies, these constructor-made viruses could usually be detected generically, for they are made from ready blocks and known polymorphic engines. Popular constructor tools include VCL, SennaSpy, BWG, PS-MPC, TPPE, and IVP. Podrezov, A. F-Secure Virus Descriptions: Constructor. [Online, May 24, 2004.] F-Secure Website. http://www.f-secure.com/v-descs/virmaker.shtml.