In today's world, it has become virtually impossible to write software without using open source tools, libraries, or frameworks. Even if you avoid "third party" open source components, Microsoft is open sourcing more of .NET so it's practically inescapable. Should you be worried? Didn't Steve Ballmer tell us open source was bad and dangerous? Well, there are things you should know about open source in terms of licensing, maintainability, support. Many are things you need to think about when using any code you didn't write yourself, whether open source or not. By the end of this session, you'll understand where open source does and doesn't differ from traditional proprietary tools, libraries, and frameworks. You might still be worried, but at least you'll understand why you're worried.