No, Hello is not part of manycams. It is part of Firefox. It allows you to have audio and video conversations over the internet. As there's video involved, it'll grab your camera and display that when you first open a conversation so you can check your self-image before having others join the conversation. I'm guessing that Hello will be picking up whatever manycams provides to it - as manycams seems to put itself in place of your normal camera driver.