(02-02-2015, 09:15 PM)Eclipse Wrote: To create them, you have to understand what they are. If you know the language, I can't imagine that it'd be too difficult.
Eclipse is correct. However, I'd say that knowledge of your desired programming language will not be nearly enough to develop some fancy and effective malware.
As for any problem you want to solve, you have to figure out HOW to solve it. No programming language will do that for you. Programming languages are but a medium for which you can express your solution. You need to understand all of the elements that come together to create a piece of malware. Will your malware require networking functionality? The ability to remain undetected? Or maybe you're designing ransomware or something pointlessly destructive.
If you're already a programmer, the most important part in my opinion is learning the platform that you're working with. If you're working with Windows, start learning all about Windows. Learn the weak points, how you can "trick" the system, how the OS handles particular tasks, etc. There are many, many books surrounding these topics and you'll be able to find them easily with a bit of Googling.
Another useful thing you can do is study malware of the past and present. Read source code, read analyses, blah blah. Don't forget to learn about how anti-viruses and firewalls work. They can be a bit of a nuisance if you haven't any knowledge of evading their detection.
Hope this helps a little, at least. Good luck.