Google has started flagging websites that don't have what is called a SSL (Security Socket Layers) Certificate .
Why is this important? If you don’t implement SSL a secure connection cannot be established. This means that sensitive information is not encrypted opening up the possibility for cyber criminals to capture that data. Google will also show your visitors a “Not Secure” warning upon visiting your site.
Once you have SSL, the address bar of the browser will show a green icon indicating to the visitors that your site is secure. So be sure secure your site today!