I recently downloaded Avast Antivirus and installed it on my computer. Does this also serve as firewall?
Avast antivirus does not include a firewall. A number of firewalls work well with avast!, some freeware and some paid versions. Some avast! users prefer Zone Alarm or Comodo. You can find more information about using different firewalls with avast! by using the search function.
Firewall tests for comparison can be found at http://www.firewallleaktester.com/tests.php
More information regarding free firewalls at
http://www.thefreecountry.com/security/firewalls.shtml
You can find an enormous amount of information about using avast by browsing the forums, especially the sticky topics at the top of each forum. (The avast! “help” files and FAQ on the avast! website are also very informative.)
I’m waiting the day that we would be able to say ‘yes’, I mean, when Alwil has a standalone firewall for us.
Anyway, personal Firewall Tests & Results can be found here http://www.matousec.com/projects/windows-personal-firewall-analysis/leak-tests-results.php#firewalls-ratings
I’d like to suggest Comodo 8)