They call this a "primer" and it will tell you the basics but it also serves as a really useful repository of things like audio formats, lossy vs lossless compression and so on.
For what it's worth.
The Department of Homeland Security announced today that they have created a "Cyber Alert System" to deliver "timely and actionable information to better secure their systems" (their words). The press release is available here. They talk about providing "products" which are really just emails: bi-weekly tips for the non-techie, bi-weekly bulletins and summaries for the techie, and Alerts (in two forms, one for the non-techie and one for the techie). You can sign up for these at http://www.us-cert.gov/.
I know, I subscribe to the CERT mailings and to the Secunia alerts.
Upate 19:47: Turns out that the Homeland's updates are done in concert with CERT. Got an email from CERT shortly after I published this entry explaining this.
I had the good fortune of upgrading my wireless setup to the D-Link DI-624 wireless router and their DWL-G650 PC card a little while back. Everything's been running quite well. The connection at home's been running at the rated 108Mbps (yeah, I know, that's not a real data rate) and I've connected to some public 802.11b access points (one at MoonBeans Coffee and a couple of McDonald's installations) as well as some friends' houses so this weekend I decided to apply the WPA update from Microsoft to see how it works.
What a disaster! I searched Google and couldn't turn up any magic bullets and wrestled with it for over 24 hours, including just uninstalling the update and nothing would restore the stability I'd had earlier. The only oddity I'd seen before the WPA update was an inability to connect to anything outside my PC after a resume from hibernation if I left ehe card in when I powered back up. Not a big deal, really -- I'd just pop the card out and reinsert it and everything would be fine. After the update I'd periodically lose connectivity and be unable to restore it (I'd get associated with the AP but wouldn't get an IP address). Only recourse was to reboot. And this continued after I'd uninstalled the update.
Fortunately, I'd created a System Restore point before installing the update (just because you're paranoid doesn't mean they're not out to get you). I restored and now everything's back to normal. Hope it stays that way.
Now, wouldn't you think the WPA update would've created a System Restore point itself? Moral of the story: never assume Windows will do something that you can do for yourself.