Many novice webmasters face a number of difficulties mastering the technical terminology of the World Wide Web. At the same time, it is important not only to understand the meanings of the terms, but also to know the peculiarities of their use, synonyms and principles of work of those things that these terms describe. Then it will be easy and pleasant to "join" the team of experienced webmasters.
In simple terms, the domain is the main part of the site address. For example, Yandex has a domain - yandex.ru. When you type this address into the address bar of your browser, the server directs you to the site corresponding to this domain. It can be compared to a taxi ride: you give the address and they take you to the indicated house. The domain is part of the generic URL.
URL (Uniform Resource Locator) is the technical name for the complete site address. In Russian, the word "url" is often used.
The subdomain, in turn, is a child domain in relation to the main one. For example, the address of the Yandex. Maps service has the address maps.yandex.ru, where maps is a subdomain (third-level domain), yandex is the main domain (second-level domain), and ru is the domain zone indicator (first-level domain). It may seem complicated, but in fact, this whole system has a fairly simple hierarchy.
Why are subdomains needed?
The Internet is a huge accumulation of information, which is why a domain structure was developed that makes it easier and faster to access this information. The domain zone can indicate both the belonging of the site to a particular country (ru, ua, by, kz), and the nature of this site - commercial (com), network (net), non-commercial (org) and a number of others.
Previously, the.net domain was only used by network providers and hosters. Today this domain can be used by anyone.
At the same time, large sites, which have thousands and even hundreds of thousands of pages, try to structure them in a user-friendly way, placing separate sections of sites on separate subdomains. This is convenient: it is easier for the user to remember and type an address like maps.yandex.ru than yandex.ru/services/maps. It also allows you to evenly distribute the load on the servers that serve such sites.
By the way, the full address of a site consists not only of a domain - despite its seeming simplicity, it is a whole "constructor" of elements, each of which plays its own role.
Parse the site address "into molecules"
Let's take the abstract address of a theoretical site as an example and consider what it consists of. Once you understand the structure of an address, it will not be difficult for you to apply it to any other address.
subdomain.site.com/pages/information.php?id=12345&type=abcde#paragraphhttps:// - this part of the address indicates the protocol through which data is transferred from the site to your computer. Without going into technical details, we note that most information on the Internet is transmitted via HTTP - the Hypertext Transfer Protocol.
subdomain is a subdomain of the site.
.site is directly the address of the main domain of the site.
.com - domain zone.
/ pages / - subdirectory on the site. For example, if a site publishes articles on different topics, then each topic can be stored in its own subdirectory.
information.php - directly the page that contains the information the user needs.
? id = 12345 & type = abcde are the so-called dynamic address parameters. They provide the page with specifying information to display - for example, the language in which it should be displayed, the name of the users, or something else. In this example, the id parameter passes the page the value 12345, and the type parameter passes the abcde value.
#paragraph is the so-called anchor, which indicates exactly which place on the page itself should be automatically navigated to. For example, if the page is large and has many subheadings (as in Wikipedia), then the anchor will immediately take the user to the desired paragraph.
This is how such a familiar and seemingly trivial address of any page on the Internet works.