Question

what is the difference between internet & intranet

Answer 1

The internet is a broad public network that anyone can access through an internet service provider while in contrast, intranet is a private network maintained by an organization for the use of its own employees, members or those who are explicitly permitted access.  

Answer 2

Internet is a interconnection of network which is share to every part of the world.
Intranet is a interconnection of network that can be accessed only to certain extend only be authorized people.