1. Security updates to products are often referred to as "patches" because they fix one small part of the product rather than updating the entire product. Analogy: Imagine that you are in a rubber raft that seems to be sinking. You look around on the boat and see small holes. You use your patch kit to fix the small holes rather than building yourself a new boat. Key point: The software you are using today likely has security holes that nobody has discovered yet. It seems unlikely, but this has been the historical precidence, whether you are using open-source (e.g. Linux), Microsoft products, or class UNIX systems (e.g. Sun). Therefore, if you don't keep up with the latest software, you will eventually get hacked. From Hacking-Lexicon