In computer networking, what are the major types of networks (such as LAN, MAN, WAN, and PAN), and how are they typically distinguished?

Introduction / Context:
Networking literature often divides networks into categories based on their size and geographic scope. The most commonly cited types are PAN (Personal Area Network), LAN (Local Area Network), MAN (Metropolitan Area Network), and WAN (Wide Area Network). Interviewers may ask you to name these and briefly explain how they differ to check your understanding of basic network classification.

Given Data / Assumptions:

• PAN involves very short range connections around a single person or device cluster.
• LAN covers a small area like an office, home, or campus.
• MAN covers a city or large campus environment.
• WAN spans large geographic regions, countries, or the globe.

Concept / Approach:
These network categories are primarily defined by geographic scale and ownership. A PAN might consist of Bluetooth devices, wearable gadgets, and a smartphone. A LAN connects computers and servers within a building or close group of buildings and is often owned by a single organization. A MAN connects multiple LANs across a metropolitan region, sometimes using high speed fiber infrastructure managed by a carrier or city authority. A WAN connects multiple distant sites, possibly across continents, using leased lines, MPLS, or public internet links. Distinguishing networks in this way helps in choosing technologies, media, and protocols appropriate for each scale.

Step-by-Step Solution:
Step 1: Define a PAN as a Personal Area Network, typically a few meters around a person, often using Bluetooth or short range wireless. Step 2: Define a LAN as a Local Area Network, covering a limited area such as an office floor, building, or campus, usually under one organization's control. Step 3: Define a MAN as a Metropolitan Area Network, connecting multiple LANs across a city or metropolitan region. Step 4: Define a WAN as a Wide Area Network, interconnecting MANs and LANs across large geographic areas, up to international scale. Step 5: Emphasize that the main distinguishing factor is physical coverage and often the ownership or management model.

Verification / Alternative check:
Examples from real world deployments illustrate these distinctions. A home Wi-Fi network is a LAN; a company campus with several connected buildings is also a LAN. A city wide fiber network connecting multiple public institutions is typically a MAN. An enterprise private network connecting branches in multiple countries over leased lines or VPNs is a WAN. These practical examples confirm that the categories are based on range and scale of interconnection rather than on specific protocols or brands.

Why Other Options Are Wrong:
Option B wrongly treats these terms as cable brands instead of network types. Option C incorrectly associates them with Wi-Fi security standards, which are separate concepts. Option D describes application layer protocols used by web browsers, but LAN, MAN, WAN, and PAN are about network topology and scale, not application protocols.

Common Pitfalls:
Learners sometimes confuse LAN and WAN simply as "internal network" and "internet" without understanding that many private WANs exist that do not rely on the public internet. Another pitfall is ignoring newer categories like CAN (Campus Area Network) or SAN (Storage Area Network); however, for introductory interviews, knowing PAN, LAN, MAN, and WAN with their approximate coverage is usually sufficient.

Final Answer:
The major network types are PAN, LAN, MAN, and WAN, distinguished mainly by geographic coverage: PAN for a person or room, LAN for a building or campus, MAN for a city, and WAN for large regions or countries.