Explaining Domain Name Extensions

A domain name extension is the suffix or last part of a domain which follows after the dot. Examples of domain name extensions include .com, .co.uk, and .net. Many different extensions exist, including country specific domain extensions such as .us, which indicates an American site, .de for Germany and .cn for Chinese websites. You do not necessarily have to live in a particular country to register a domain with a country specific suffix. The most common extension is .com, which represents commercial websites. It is widely used in America and many other countries.

Website domain names are allocated on a first-come, first-served basis. So to a certain degree, the choice of domain name extension may be limited to availability. Let's say that you would like to register a domain called "mywebsite". You would first need to search on a domain registry website to check names and extensions available to register. You may find that "mywebsite.com" was already registered, but that you could select "mywebsite.biz" or "mywebsite.co.uk". You should give careful thought to the viability of a new website if another one of a similar name already exists, even if the suffix is different. This could cause confusion to visitors, as they may not realize that two websites with the same name, but different extensions may not be run by the same company.

A country specific domain extension should also be considered, as it will help visitors identify a website containing relevant and local information. Certain country specific domain name extensions may only be registered by residents of that country. Registrants of .us domains must be United States citizens, residents, or organizations, or a foreign entity with a presence in the United States.

 Search engine results can often return over a million web pages. It can be frustrating when you click on a few results, only to find they are selling products not available in your country. If you were a UK resident, you would assume that a domain with a .uk extension was British, and would be most likely to select that one if listed in the results. In addition, one of the factors used by search engines such as Google is to prioritize local results, so that a .uk extension may appear higher than website domains with other extensions.

A further aspect to help explain domain name extensions in relation to search engine optimization is the use of the domain extension as a keyword. In order to narrow down search results, a potential visitor to your website might use a keyword phrase containing the country, for example "dolphin trainers us". When the domain extension is .us, this helps give the website a priority in search engine results. When the visitor sees the US domain extension, they will be more likely to click through to the website, as they know it will be an American site.

Idcwebs, Understanding Web Extensions

Neustar, US Nexus Requirement

SEO Book, Does Domain Extension Matter?

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