Viruses

[Suchy]

Can someone explain me the brains behind viruses, adware, crapware...

Why do people make them, and what does it do for them?

[PrntRhd]

It used to be hackers who used them to break into systems, now it seems to be organized crime who pay hackers to infect PCs, steal financial information and plunder the compromised accounts. Identity theft is also lucrative, they open credit card accounts in the name of the targeted victim.
Adware also is lucrative, the purveyors get paid per view on ads, infecting a PC gives advertisers a captive audience. Affiliates get paid per machine they infect.

[pop pop]

By and large, the intent is no longer to just bring systems to their knees. As PrntRhd points out, the motivation now is money and how to make it. Legal means to make money are always more work and more difficult. So criminals, being what they are, resort to easier methods like stealing--your money, your PC, your account numbers, your identity.