There are several types of networks that are used for different purposes. Some of the most common types include:

Local Area Network (LAN)

A Local Area Network (LAN) is a computer network that connects devices, such as computers and servers, in a small geographical area, such as an office or home.

Usage:

• Sharing resources such as printers, files, and internet connection among the devices connected in the network.
• Facilitation of communication between devices connected in the network.

Advantages:

• High-speed data transfer and low latency.
• Easy to set up and manage.
• Ability to share resources and peripherals such as printers and scanners.
• Cost-effective solution for small businesses and home networks.

Disadvantages:

• Limited geographical reach, only devices within the same physical location can connect to the network.
• Security risks, as the network is confined to a small area, it is easier for unauthorized access and breaches.
• With limited scalability, adding more devices to the network can slow it down and cause other problems.

Examples:

Home Network, Office Network, Small Factory Network, Hotel Network, etc.

Metropolitan Area Network (MAN)

A Metropolitan Area Network (MAN) is a network that connects devices and networks within a metropolitan area such as a city.

Usage:

• It is used to connect devices and networks in a city or a metropolitan area, it allows for communication and resource sharing among the devices and networks that are not in close proximity.

Advantages:

• It allows for communication and resource sharing among devices and networks over a wide geographical area
• It can be connected to other networks to provide Internet connectivity
• It provides a higher level of security than a wide area network (WAN)

Disadvantages:

• It can be expensive to set up and maintain
• It requires specialized knowledge to set up and maintain
• It is less secure than a LAN (Local Area Network)

Examples:

Public transportation systems, Public Wi-Fi networks, Public safety networks, Smart City networks, Educational Institution networks, etc.

MANs are typically used by organizations that need to connect multiple sites within a city, such as government agencies, large businesses, and educational institutions. They can also be used to provide Internet access to a specific area, such as a business district or residential neighborhood.

Wide Area Network (WAN)

A WAN (Wide Area Network) is a type of network that connects devices and networks over a large geographical area, such as a city or country.

Usage:

• Connects LANs or other networks together over a large geographical area, such as a city or country.
• It allows for communication and resource sharing between devices and networks that are not in close proximity.
• It is commonly used in organizations with multiple locations, remote employees, or branch offices.

Advantages:

• Can connect devices and networks over a wide geographical area
• Allows for communication and resource sharing between remote devices
• Can be used to connect remote offices and branch locations
• Can use different technologies such as leased lines, satellite, or internet

Disadvantages:

• More expensive to set up and maintain than LANs
• Can be more complex to set up and manage
• Can have higher latency and lower speeds than LANs
• Can be vulnerable to security risks if not properly configured and maintained
• May require specialized knowledge to set up and maintain the network.

Examples:

The Internet, Corporate networks, Virtual private networks (VPNs), Cellular networks, Satellite Networks, etc.

Personal Area Network (PAN)

A Personal Area Network (PAN) is a network that connects devices and peripherals that are close to a person, usually within a range of 10 meters.

Usage:

• PANs are typically used to connect devices such as smartphones, laptops, tablets, and personal assistants.
• PANs can be wired or wireless, and are often used for data transfer and device synchronization.

Advantages:

• Convenient and easy to set up.
• Allows for easy transfer of data and files between devices.
• Enables device synchronization.

Disadvantages:

• Limited range and coverage area.
• Can be affected by physical barriers, such as walls.
• A limited number of connected devices.
• Security can be a concern as the devices are usually not protected by firewalls and other security measures.

Examples:

Bluetooth, Wireless headphones, Wireless charging, Smart home devices, Wearable devices, etc.

Storage Area Network (SAN)

A Storage Area Network (SAN) is a specialized, high-speed network that connects storage devices, such as disk arrays and tape libraries, to servers.

Usage:

• SANs are typically used in enterprise environments to provide centralized and dedicated storage resources.
• SANs can also be used to facilitate data backup and disaster recovery.

Advantages:

• SANs provide dedicated storage resources and high-speed data transfer.
• SANs can improve data availability and disaster recovery.
• SANs can also improve storage scalability and management.

Disadvantages:

• SANs can be complex and expensive to set up and maintain.
• SANs require specialized knowledge and expertise to manage.
• SANs can be vulnerable to data loss and corruption if not properly configured and maintained.
• SANs are typically used only in enterprise environments and may not be a cost-effective solution for small businesses or home users.

Examples of Storage Area Networks (SANs) include:

1. Fibre Channel SANs: Fibre Channel SANs use a dedicated high-speed Fibre Channel (FC) network to connect storage devices to servers, allowing for fast data transfer and high availability.
2. Internet SCSI (iSCSI) SANs: iSCSI SANs use IP networks to connect servers to storage devices, allowing organizations to leverage their existing Ethernet infrastructure to create a SAN.
3. Network-attached storage (NAS) SANs: NAS SANs use file-based protocols such as NFS or SMB to connect servers to storage devices, allowing for easy data sharing and collaboration.
4. Storage over IP (SoIP) SANs: SANs that are built on top of TCP/IP infrastructure such as Fibre Channel over IP (FCoIP) or iSCSI are also considered as Storage over IP (SoIP) SANs.
5. Object storage SANs: Object storage SANs uses object storage protocols like S3 and OpenStack Swift to connect servers to storage devices, and allows for unlimited scalability and durability.

Global Area Network (GAN)

A Global Area Network (GAN) is a type of mobile network that connects devices and users worldwide.

Usage:

• GANs are typically used by cellular providers to offer mobile internet and other services to users.
• GANs can be used to connect devices such as smartphones, tablets, and laptops to the internet and to other devices.

Advantages:

• Provides connectivity to users globally.
• Allows for communication and data transfer between devices worldwide.
• Offers mobility and flexibility to users.
• Can be used to access the internet and other resources from anywhere in the world.

Disadvantages:

• Can be expensive to access and use.
• Can be affected by poor signal quality or coverage in certain areas.
• Security can be a concern as the devices are usually not protected by firewalls and other security measures.
• Can be affected by network congestion, resulting in slower data transfer speeds.

Examples:

1. The Internet: The Internet is a global network of interconnected computers and devices that can communicate with each other using standardized protocols.
2. Global satellite networks: Global satellite networks use a network of satellites in geostationary orbit to provide coverage to remote or hard-to-reach locations, such as ships at sea or oil rigs in the middle of the ocean.
3. Global cellular networks: Global cellular networks use a network of terrestrial and satellite-based cell towers to provide coverage to mobile devices in multiple countries.
4. Global private networks: Global private networks are used by large multinational corporations and organizations to connect their offices and facilities in different countries, allowing for secure and reliable communication and data transfer.
5. Global satellite-based navigation systems: GPS, Galileo, GLONASS, BeiDou, and NavIC are global satellite-based navigation systems that provide location and time information to users around the world.

Note: GAN is not a well-established term, it is not widely used. Instead of GAN, people use the term "Global System for Mobile Communications(GSM)" which is a standard for mobile networks and provide mobile communication services worldwide.