What is a Network?

Before diving into networking, we need to understand what a “network” is. In Burmese, a network is referred to as "ကွန်ယက်", which generally means a group of interconnected devices. These devices can connect and communicate with one another to share resources and data.

Devices in a network can include computers, mobile phones, and also the components that help facilitate connections—like cables, wireless routers, servers, switches, and printers. When these components work together to enable communication between devices, it's called networking. The actual system of connected devices is called a network.

Now, why do we need networking? This is an important question—especially for aspiring hackers and cybersecurity professionals. You can't just ask "what is it?"—you also need to ask "why is it used?" Only then can you begin to understand "how it works." Even if these concepts seem complex now, they will become clearer over time.

The history of computer networking dates back to the late 1950s, initially developed for the US military. One of the first major advancements was ARPANET (Advanced Research Projects Agency Network), introduced in 1969. ARPANET was the first packet-switched network in history and laid the groundwork for today’s internet. It was developed by ARPA, a part of the U.S. Department of Defense.

Due to geopolitical tensions during the Cold War, the U.S. sought more resilient communication systems in the event of nuclear strikes. Traditional centralized communication systems were vulnerable, so the decentralized approach of networking proved to be more reliable and secure.

In earlier times, networks relied on direct, dedicated connections—called circuit-switching. This made them vulnerable to failure if any connection was broken. ARPANET introduced packet-switching, where data is split into small packets and routed dynamically. This technology greatly improved reliability and is still used today.

Along with packet-switching, the development of the TCP/IP protocol suite enabled the creation of standardized rules for data transmission and communication between different types of devices. This protocol suite is the foundation of modern internet communication.

Thanks to these developments, what started as a military communication solution eventually evolved into the modern internet. Today, we all use it regularly. Let's now explore the purpose and benefits of networking.

Networking allows devices to share files, documents, and various types of data. It also enables the shared use of resources like printers and storage systems. This makes resource management more efficient. We also use networking for emails, messaging, voice and video calls—tools we rely on daily. These are some of the core benefits of networking.

The process of connecting devices together is called networking, and the resulting system is called a network. Based on size and reach, networks can generally be categorized into three main types: LAN, MAN, and WAN.

LAN (Local Area Network): A small-scale network typically used within a limited area like a home, office, or shop. For example, all the computers in an office might connect to the same printer through a LAN. If you're using the same Wi-Fi network at home, all connected devices form a LAN. Devices within a LAN often share the same IP class and can communicate directly with each other. For instance, if you host a local website using Apache on your computer, other devices on the same Wi-Fi can access it, but outsiders cannot unless additional configurations are made.

MAN (Metropolitan Area Network): A larger network that connects multiple LANs across a city or a metropolitan area. It's bigger than a LAN but smaller than a WAN.

WAN (Wide Area Network): The largest type of network, spanning countries and continents. The internet itself is a prime example of a WAN. In ethical hacking, attacking a LAN is relatively straightforward, but targeting a WAN requires more advanced techniques and tools. (For real-world examples, I’ve written a book titled “The First Step Towards Hacking” which is a beginner-friendly guide. It is Burmese book, English version is coming soon.........)

Networks can also be categorized by their architecture and purpose. There are two main types: Client-Server networks and Peer-to-Peer (P2P) networks. I won’t go into the details of these here, as this article might become too lengthy or dry if we go further for now.