The document discusses different types of computer networks - local area networks (LANs), which cover small areas like offices up to 10km in size, metropolitan area networks (MANs), which can cover entire cities up to 100km, and wide area networks (WANs), which can connect LANs across large areas like entire countries or worldwide.

5.  Security Concerns.
 Virus and Malware.
 LackofRobustness.
 NeedsAn EfficientHandler.
 LackofIndependence.

6. LAN
• Local Area Network covers the office or a big factory
area. The maximum limit is 10 Km in size.
MAN
• Metropolitan Area Network covers a city. The
maximum limit is 100 Km in size.
WAN
• Wide Area Network covers the entire world. It can
contain a group of LANs connected with each other.