How Web Addresses Break Down
A web URL (address) has several significant parts. Following is a breakdown of the various parts of a web address. An URL looks something like this: https://www.dummies.com/Section/Store.id-321213.html.
http stands for HyperText Transfer Protocol. It’s a standard that governs how web content is transmitted.
www stands for World Wide Web. This indicates that on the server you are going to be accessing, you want the section that contains the web content. This is sometimes called a subdomain.
dummies.com is the domain name. That’s the name of the website you are visiting.
Everything that comes after the domain name is a path on the server to the content you want. For example, Store.id-321213.html is the filename containing the content you want, and Section is the folder in which it is stored.
The forward slashes (/) in the address are separators.
The figure summarizes all that as a quick reference.
The last part of a domain name (the part after the last decimal point, like com in dummies.com) is called the top-level domain. There are only a limited number of top-level domains, and each one has a special meaning that describes the type of domain. For example, com is short for “commercial.”
The table lists some of the most common top-level domains. You can use that information to tell at a glance what type of site a certain domain name represents.
|net||Network-related||Commercial sites that deal in networking or the Internet
|edu||School||Educational institutions of all levels|
|uk||United Kingdom||Sites located in the United Kingdom|
|ca||Canada||Sites located in Canada|
|Other country codes (there are many)||Country-specific||Sites located in the country represented by the code|
Domain names are human-friendly versions of web addresses. They are easy to remember, and easy to understand. But behind the scenes, domain names have another face: a numeric one. Each domain name has an equivalent Internet Protocol (IP) address.
All across the Internet, there are special servers that translate between domain names and IP addresses. These are called Domain Name Server (DNS) servers.
When your browser sends out the request over the Internet to get a particular page you’ve requested, a DNS server intercepts that request and looks up that domain name’s IP address in a giant database. It then uses the IP address to route the request to the server that contains the requested information.
There are two kinds of IP addresses: IP version 4 (IPv4) and IP version 6 (IPv6). The Internet currently uses only IPv4 addresses, but at some point in the future, it’s going to switch over to IPv6 addresses, a newer type of addressing that has more possible addresses.
An IPv4 address (pronounced I-P-V-4) is four numbers, each of which is between 0 and 255, separated by decimal places, like this:
An IPv6 address is six numbers, written in hexadecimal (base 16) numbering, separated by colons. Here’s an example:
You’ll probably never need to know any more — or even that much — about IP addresses, unless you find yourself in the unfortunate position of troubleshooting a network problem or talking to tech support for your Internet service provider. (Well, actually both of those situations do come up fairly frequently in life, so now you’re equipped for those possibilities.)