anti-virus sheild or firewall?

Can somebody please explain the difference to me?
the last time I installed a firewall, I ended up with a windows protection error with ndis.vxd, which resulted in me re=installing windows(98). since then I have installed an anti-virus programme that seems to be keeping me "safe"
Do I need a firewall?
Thanks in advance for any help

 

A firewall protects you from hackers attempting to control, or do harm to, your system. An antivirus program protects you from that which you allow past your firewall that may contain malicious code that, if executed, may do harm to your system.

 

Basically, yes.

AV will only protect whats on your system already. However if someone attempted to get into your machine, the AV will not nececarily detect this.

A Firewall will make your machine "hidden", so to the casual hacker thinks there is no machine at your IP address. It can also prevent programs from accessing the internet (e.g. a Trojan virus).

In order to have effective protection, you need both. Some AV programs have both built in, for example Mcaffee, Norton and Panda antivirus all have intergrated firewalls, in which case you do not need another seperate firewall program.

 

Re: software firewalls. It's been a long time since I used one (tried several, actually, back in the day), and, unless substantial improvements have occured, I would have to recommend a hardware firewall, such as that provided by a router, to do the job for you. These days, routers are so cheap, it's an easy choice.

 

That all depends on the setup though. If we're talking a 56k connection.. its really not gunna be worth the hassle to get hardware. If you're on DSL or Cable then yes a simple router would be good protection.

But then, hardware firewalls arn't foolproof, as they cant block programs connecting that are already on your machine, such as trojans, dialers etc. as they cannot distringuish them from a legit program (such as Internet Explorer) but a software firewall can, and you can set up rules for what programs can and cannot access the net.

 

to goldfish and the doug
many thanks fellows, alas I don't know what a router is, except in woodworking, it's a brilliant tool that makes a lot of noise, sawdust and wastewood, worth every penny!
Anyway, I've downloaded another firewall programme from MG, but before I even did this I did a total backup of my C: drive, then copied ndis.vxd(my enemy) to a floppy, then backed up my system files to a zip disc. If my installation should go tits up, will I be able to get back to normality?
Whilst i was backing up etc. I came across two files win.com and wsock32n.dll their details didn't match the others in my system files; are they supposed to be there?
once again, many thanks in advance