What information is needed in choosing a webcam for your computer?

I am trying to purchase a webcam for my computer. The person who is trying to sell me the webcam asked me what the brand of computer is, the type of windows (xp, vista etc...) and then asked the model number and year. Is this too extensive of information to be giving fo just the purchase of a webcam or is this information needed?|||No, that makes sense -- you need to know what type of operating system as well as the model #. Otherwise it might not be compatible and that would be a bummer, right?|||Only the machine type and OS is required. For a great guide to webcams read this article (http://mailVU.com/blog/which-webcam-shou鈥?/a> It describes the features and specifications to look for in a webcam, and recommends specific models with built-in mics starting under $25.