Overview of Networks

A network is a system that links two or more computers together to share resources.
The major components of a network are hardware, software, and network communication protocols.
Hardware includes devices used for input/output (I/O) operations as well as devices that store information.
Software involves operating systems, network operating systems, as well as applications that run on the network.
Protocols are the rules and formats that the network follows to enable communication between devices.

Types of Networks

Networks could be Local Area Networks (LAN), Wide Area Networks (WAN), or Personal Area Networks (PAN).
LAN is a network that covers a small geographical area such as within a building.
WAN is a network that covers a large geographic area and may span countries or the globe.
PAN is a network covering a very small area, typically within reach of a person.

Network topology describes how devices are interconnected in a network.
Star topology, Bus topology, Mesh topology and Ring topology are major types of network topologies.
The star topology has all devices connected to a central hub or switch. A problem in one device does not affect the others.
In bus topology, all devices are connected to a central backbone. If the backbone fails, all devices lose connection.
Ring topology has devices connected in a circular format. Information travels in one direction causing potential data collision.
In mesh topology, all devices are interconnected. It provides multiple paths for data transmission, improving reliability.

Protocols are a set of rules for communication over the network.
TCP/IP is the most commonly used protocol suite on the Internet. It encompasses several protocols such as HTTP, FTP, SMTP, and more.
The HTTP protocol is used to view web pages over the Internet.
FTP is a protocol used for transferring files over the Internet.
SMTP is a simple mail transfer protocol used for sending messages.

Wireless networking uses radio waves to transmit data. It has made mobile and remote access to networks possible.
Wi-Fi is the most common form of wireless networking.
Bluetooth is a short-range wireless technology often used for connecting peripherals to a computer.

Networks can be vulnerable to security threats such as malware, hackers, and data breaches.
Common security measures include firewalls, password protection, and encryption.
A firewall protects the network by monitoring and controlling incoming and outgoing network traffic based on predetermined security rules.
Encryption is the process of encoding information so only authorized parties can access it.
Regular data backups, updates, and patches are also crucial for maintaining network security.

Networks enhance communication, data sharing, and resource allocation.
They can also facilitate remote working and learning.
However, network systems can be expensive to setup and maintain.
They can also become complicated as they grow, requiring professional management.
Networks are subject to security risks, and system failures can disrupt work.