Does Lion come with Firewall?

Several weeks ago I upgraded to OS X Lion. Does it come with a firewall I can protect my iMac with? Or does a Mac even need a firewall... or do I need to purchase an external firewall.
Thanks.

Click on System Preferences. Under the Personal Section, click on Security and Privacy, then click on the Firewall tab. I can't remember if the default is on or off, but if off, turn the firewall on.

All computers need firewalls. Once your firewall is on go to the Shields Up website and test it out https://www.grc.com/x/ne.dll?bh0bkyd2

Leave it OFF unless you are connecting at a public site.

This is not a Windows PC.

If you have a router at home, you more than likely already have a hardware firewall. I've not seen any good reasoning to also turn on any software based firewall in OS X or in Windows.

harryb2448 said:

Leave it OFF unless you are connecting at a public site.

This is not a Windows PC.

Click to expand...

And ill +1 this comment from my mate harry.
There is no need for a firewall using your Mac. If your inter web surfing is safe and you DONT enter your ADMIN password when asked to and when you are not sure why it asked, then you are as safe as can be.

Cheers