I just read a great article in Fortune magazine about hackers and cyber security called Surviving a Hack Attack.  The article is actually an advertisement by Kroll, a risk consulting company, but is well written and has some very valuable tips.  Here are the main lessons from the article that i think everyone should follow:

1. Keep your computer antivirus and software patches up to date.
2. Don’t divulge sensitive information on social media.
3. Make sure corporate laptops are encrypted, and never leave a laptop unattended in a public space.
4. Never open unknown attachments or click on unverified email links.
5. Use different passwords fro different accounts, change passwords regularly, and make sure they contain a combination of numbers and uppercase and lowercase letters.

I highlighted in BOLD the points that I think are absolutely critical.  I have personally witnessed many instances where computers were hacked because these simple rules were not followed.