[dba-Tech] Discussion/explanation of security bulletins from MS

I get the security and download bulletins from MS. I try to read them, but they make no sense to me whatsoever. Perhaps a discussion here might help shed some light on what I'm supposed to get from these bulletins? I don't even know what questions to ask. Every item seems to deal with some technology I've never even heard of, so it's hard to determine if it's something I really need to bother with -- as yet, I've not done a thing based on anything I've read in one of those bulletins. I'm sure I misunderstand the bulletin's purpose. 

Susan H.