VPN is "Virtual Private Network", that is usually what universities and other agencies use to set up a secure private link for those outside their network to log in. For instance, if you work for a large corporation, or say a University, they likely have their own closed intranet that generally cannot be accessed by the general public. However, through VPN you can get on their system. It's one way. There are others. Secure tokens are another. I don't know what PPTP or L2TP are.
Actually, I've been working with Macs a long time, and I'm not familiar with XCode 2, but what I can tell you is that in OS 10.4 you can turn on the Firewall. Go the the apple pull down menu in the upper left corner and choose System Preferences and click the "Sharing" icon. When that opens, there is a choice for "Firewall", turn it on. If you are not using your computer for sharing, turn off sharing and Appletalk. In fact, under "services" same Sharing menu, turn off everything remotely linked to sharing. That helps.
If you use Safari for browsing, on the Safari pull down menu, there is a choice for "private browsing", use that.
If you use Firefox, there are a number of things you can do. Under the Firefox pull down menu, chose preferences, then choose privacy. Turn off "accept cookies from sites", if you like, but put the web pages that you use frequently and trust, put on as exceptions so you aren't prompted constantly, then turn on "Always clear private data when I close Firefox". Also under preferences, chose security, and turn off remember passwords and master password, turn on "Tell me if suspected web sites are forgeries" and "warn me when trying to install add ons?.
That stuff will help. It's true there aren't as many viruses and spyware for the Mac, but as the market share increases, and as Steve Jobs continues to piss off the general public, this could all certainly change in the future. I've seen the evolution of Apple over the years. Apple is slowly but progressively becoming more like Microsoft, so I think in the end, it will be a wash in terms of safety. Who knows when, but one of these days.
