Japanese
Internet = Traffic Network
The Internet is an order formed upon existing media of various sorts and kinds. It resembles road system.
Road system is made of all sorts of road. There is a highway and there is such a road as we are tempted to call "divider of buildings". We cannot define "road" by means of form and quality. It is a traffic rule that provides for "road". Roads are "roads" because they are used in a fixed manner. For examle, a road can be temporally made in a ground. This shows that "road" is not substantial.
So is the Internet. The Internet is supported by various sorts of communication media. An examle of elements is a public telephone circuit. What makes those variety of media the Internet is a rule or communication. It is the "TCP/IP protocol". So "communication network ruled by TCP/IP protocol" is the logical meaning of "Internet".
In order to keep this article be "for beginners", I won't enter the details of "TCP/IP protocol".
Once again !