Its a must to have an antivirus software installed in your system. There are many softwares available out there like McAfee, Avast, Nortan, etc.
But personally to have a problem free computer experience, follow these simple tips:
Things to FOLLOW:
- Always have an up to date virus scanner running
- Always have a firewall running
- Install all the latest security updates
- Use a non-IE or IE based browser
- Delete all unsolicited emails containing attachments without reading
- Manually scan all email attachments with your virus scanner, regardless of whether it's supposed to be done automatically
- Copy and paste URLs from email messages into your web browser
- Inspect links copied and pasted into your web browser to ensure they don't seem to contain a second/different address
- Establish a regular backup regimen
- Make regular checks of your backup media to ensure it is still good
Thing NOT to follow:
- Use of Internet Explorer and any browser based on Internet Explorer (e.g. Maxathon and MSN Explorer)
- Use of Outlook or Outlook Express
- Open email attachments you haven't manually scanned with your virus scanner
- Open email attachments you were not expecting, no matter who they appear to be from
- Respond to spam messages, including using unsubscribe links
- Visit questionable websites (e.g. porn, warez, hacking)
- Poke unnecessary holes in your firewall by clicking "Allow" every time some program requests access to the Internet.
- Click directly on links in email messages
- Use of pirated programs
- Use of file sharing or P2P programs
Its better to actually follow and maintain certain things as well, rather than just depending on malware protection software.