Internet and the web... we use these terms interchangeably every day. Yet, they are two distinct concepts.
Networks
A network is a set of interconnected entities (computers, devices, or systems) that communicate with each other to exchange information or share resources.
For example, at home, your phone, computer, TV, printer, surveillance cameras, etc., are connected through your internet router.
Together, they form your private and secure home network, preventing your neighbors from accessing your data.
Your router has multiple functions. Among others:
- Managing the home network: assigning IP addresses.
- Securing the network: firewalls, parental controls, VPNs.
- Acting as a gateway to the outside: communicating with the Internet Service Provider (AT&T, Starlink...).
In the chapter on communication protocols,
we compared the Internet to a postal system with local offices and sorting centers.
Your router is like the post office of your village, the starting point of your communications to the rest of the world.
Internet
Internet is a vast network that interconnects smaller networks across the globe.
Submarine cables, orbiting satellites, relay antennas, massive data centers, and billions of connected devices form this complex ecosystem, enabling instant information transfer over long distances.
In 1969, the U.S. Defense Advanced Research Projects Agency (DARPA), created ARPANET.
It was the first large-scale network based on the concept of packet switching: breaking data into small pieces and reassembling them at the destination.
Before this, networks primarily operated on circuit switching.
This is what you see in movies depicting 1950s telephone exchange centers, where operators manually connected lines to establish a direct and private communication channel between two people.
The line was dedicated to that communication and couldn’t be used by anyone else until the call ended.
Packet switching is like sending a book page by page in separate envelopes. It allows:
- Parallelizing messages. Instead of waiting for the transfer of the entire book, we can send and receive other information between pages.
- Sending each page through different routes to optimize transfer speed.
- And most importantly, being resilient to failures on a specific route.
Resilience was one of ARPANET's main goals. During the Cold War, the U.S. aimed to develop a network that could survive partial destruction, especially in the context of a nuclear attack.
ARPANET's development introduced foundational technologies like the TCP and IP protocols,
which remain at the core of the Internet today.
Initially, in 1969, ARPANET connected four universities. It later grew within academic and scientific communities before being dismantled in 1990.
In 1983, ARPANET and other independent networks adopted the TCP/IP protocols, becoming interconnected and capable of communicating with each other.
Thus, the network of networks, the internetwork, was born.
Web
In 1989, the European Organization for Nuclear Research (CERN) was already connected to the Internet.
British researcher Tim Berners-Lee, assisted by Belgian Robert Cailliau, envisioned a tool based on the Internet to easily share scientific documents.
Essentially, his project aimed to make available what we now call a website.
He named it the WorldWideWeb, abbreviated to Web. Yes, that’s where the "www" comes from!
The idea of a "web" comes from the interconnection between pages via links, creating the impression of navigating through a web of information.
These links are called "hypertext" because they dynamically connect different resources, enabling non-linear navigation.
Unlike a traditional text, where reading follows a fixed order, hypertext gives users the freedom to choose their path, transforming access to information into an interactive and intuitive exploration.
The term "hypertext" dates back to a 1965 project that inspired Tim Berners-Lee. The concept itself stems from studies as far back as 1945, aimed at replicating the natural connections of human thought to explore information.
The name "Web," initially referring to the tool, evolved to represent the entire ecosystem of technologies developed for the project.
In particular, its three pillars:
- HTML (HyperText Markup Language): the language used to structure and display web pages.
- HTTP (HyperText Transfer Protocol): the protocol enabling communication between web clients and servers. In 1990, Tim Berners-Lee developed the first web browser, "Nexus," and the first web server, "CERN httpd."
- URL (Uniform Resource Locator): unique addresses to identify resources on the Web.
In 1993, CERN made a crucial decision: to make Web technologies royalty-free, enabling widespread adoption.
Over time, Web usage evolved, marking major milestones in its development. The Web's evolution is often divided into three phases or versions, reflecting technological advancements and changes in how we interact with information.
- Web 1.0: The "static" Web (1990s - early 2000s). This was primarily a platform of static pages where users mainly consumed information. Interactions were limited, and content was only created by site administrators.
- Web 2.0: The "social and interactive" Web (2000s - present). With the rise of blogs, social networks, and collaborative platforms, users became content creators. Web 2.0 emphasizes interactivity, sharing, and online communities. New technologies enabled smoother and more dynamic interfaces.
- Web 3.0: The "intelligent and decentralized" Web (emerging). This phase leverages advanced technologies like blockchain, artificial intelligence, and semantic data. It has gained attention in recent years, particularly with the rise of cryptocurrencies.
To summarize, the Web is an application of the Internet, just like the weather app is an application on your smartphone. Other Internet applications include email, instant messaging, file sharing, streaming, and video conferencing, some of which use protocols different from those of the Web.