The internet as a worldwide network

The internet connects computers and other devices across the globe, allowing them to communicate and share information. It forms a vast system that links smaller networks together.

Key features of the internet

• Global connectivity - The internet is a wide area network (WAN) that joins devices and local networks from different countries, enabling worldwide access to data and services.
• Network of networks - It operates by interconnecting various smaller networks.

The World Wide Web

While the internet provides the underlying connections, the World Wide Web (WWW) builds on this foundation to deliver specific types of content that users interact with daily.

The World Wide Web consists of a collection of websites that are hosted on web servers.

URLs and accessing websites

To locate and open specific content on the WWW, addresses called URLs are used. These provide a structured way to reach exact resources on web servers.

Components of a URL

A URL typically breaks down into key parts that guide the browser to the right location.

IP addresses and domain name servers

Devices on the internet need unique identifiers to communicate accurately, and systems are in place to make this process user-friendly.

IP addresses

• An IP address is a unique numerical label assigned to each device on a network, such as 192.168.50.75.
• It helps ensure that data sent over the internet reaches the correct destination.
• IP addresses are essential for routing information between networks.

Domain name servers (DNS)

• A domain name server (DNS) is a system that converts easy-to-remember domain names (like www.example.com) into their corresponding IP addresses.
• Without DNS, users would have to memorise complex IP numbers to access websites, which would be impractical.

Data transmission in packets

When information travels across the internet, it is broken down and reassembled to ensure efficient and reliable delivery, even over long distances.

How data packets work

1. Splitting the data - Before sending a file or message, it is divided into smaller units called data packets.
2. Adding destination details - Each packet includes the IP address of the receiving device.
3. Routing through networks - Packets are forwarded by routers, which direct traffic along paths to avoid congestion.
4. Independent paths - Different packets from the same file can take separate routes, allowing them to bypass busy areas and arrive faster overall.

Benefits of packet-based transmission

By avoiding a single fixed path, the system handles more data simultaneously and reduces delays from network traffic.

Difference between the internet and the World Wide Web

It's important to distinguish between the internet and the WWW, as they are related but not the same.

Key distinctions

• The internet - This is the underlying global network infrastructure, often described as an interconnected network that links devices worldwide.
• The World Wide Web - In contrast, the WWW is a specific service that runs on the internet, consisting of websites.