Q:

"The identity of this website has not been verified."

I'm using chrome on Ubuntu 12.10. There are always message from chrome :
`The identity of this website has not been verified.

Your connection to askubuntu.com is not encrypted.`

Facebook and Twitter do not appear such message. What's wrong? What can I do?

A:

Nothing is wrong, if you click the "What do these mean?" you will see 
https://support.google.com/chrome/bin/answer.py?hl=en&answer=95617&p=ui_security_indicator

The site isn't using SSL. This icon displays for http:// sites. Most
  sites don’t need to use SSL because they don’t handle sensitive
  information. Avoid entering sensitive information, such as your credit
  card information or bank login information, on the page. If sensitive
  information is being requested on a site not using SSL, consider
  contacting the website owner.

