hyperlinks :
 basic
communication device
transmission media
advantages and disadvantages

Advantages:

1) Data sharing - enable many people to access and share the same data such as database.

2) Connectivity and Communication - Network connect computers and the users of those computers.
Disadvantages :

1) Undesirable Sharing - viruses are easily spread over network and the internet.

2) Security issues - a computer hacker can get unauthorized                    access and sabotage.