if you want to know about the Viruses/spyware/etc then
this is not specific to type here.
as there are many types of viruses and all.
if you get to the wikipedia for viruses then you will find lots of virus description...
This is not helpfull to us untill we want to create the Anti virus.
the vireuses and all are classified in various field:
Trojen horse, Win32 virus etc...
ehile trojen horse delete the imp file and create shotcuts of 1kb and all that and many more....
So i advice you to go for Wikipedia.
If you are using Avast Antivirus then click on Virus information You will find atleast 5-6 viruses from initial letter (ex: a, b, c, d, ... x, y, z)
It's amazing what you will find if you simply type your question into Google and search it. Forums are not the place for general questions.
If you want to learn about viruses, surf a few porn sites.
Following the recent ransomware attacks that leveraged the WannaCrypt0r malware and NSA-developed EternalBlue vulnerability exploit, there was plenty of advice that backup, backup, backup was the best mitigation. Data backups ...