Http
Https
http stands for HyperText Transfer Protocol 
https stands for HyperText Transfer Protocol Secure
The url starts with http://
The url starts with https://
Http communicates to port 80.
Https communicate to port 443.
Used for Normal information exchange between the client browser and web server.
Encrypts the information before sending from the client browser to web server.
Information related websites uses this protocol.
Emails, Online shopping websites, Banking websites, payment gateway, and social networking sites uses https protocol.
SSL certificate not required
SSL certificate essential in case of online shopping