HTTP stands for Hyper Text Transfer Protocol and it is an communication protocol. Shortly, HTTP can be thought of as a key that allows us to connect to websites. And there is HTTPS. It means Secure Hyper Text Transfer Protocol. HTTPS makes the site you visit secure as it encrypts the data exchange between the user and the server.
In summary, all sites with https:// at the beginning have SSL certificates, they protect your informations against possible security problems.
I didn't even know about this before; I knew what HTTP stood for but never bothered about the 'S', this is a real eye opener. Thank you for sharing this.