The Top-Level Domain (TLD) is the last segment of a domain name – the letters immediately following the final dot. These TLDs can be generic (.com, .net, .edu, .org) or country-code (.uk, .us, .de, .in) which are geographically specific. The TLD in question here is GB.
The .gb is a country code top-level domain (ccTLD) for the United Kingdom. It is based on the ISO 3166-1 alpha-2 country code for the UK, which is “GB.” However, the .gb domain is not actively used or commercialized, that is why it may seem unfamiliar.
As per the Internet Assigned Numbers Authority (IANA), the entity responsible for global coordination of the DNS Root, IP addressing, and other internet protocol resources, the .gb domain is listed as being reserved for the UK, but it is not open for registration. It’s theorized that this is because “.uk” is far more recognized and used as the ccTLD for the United Kingdom.
To put it differently, since .uk is more commonly accepted around the world, and it’s also more recognizable to people within the UK, it’s far more practical to use .uk rather than .gb.
The .uk TLD was introduced in 1985 and has been widely used ever since. The .gb was actually also delegated in 1985, but was never used to the same extent and has since essentially fallen out of use.
Despite the lack of use, .gb has not been officially retired or removed from the list of ccTLDs, so while it’s not currently in use, it hasn’t been deleted from the Domain Name System (DNS).
In a nutshell, the country code top-level domain .gb exists in theory, but not in practice. The preferred ccTLD for the United Kingdom is .uk, and .gb isn’t open for registration and isn’t used in active websites.
In terms of recognized sources, the information above reflects data from The Internet Corporation for Assigned Names and Numbers (ICANN) and IANA, which are key bodies in the governance of internet domain structures.
SOURCES:
1. Internet Corporation for Assigned Names and Numbers. “ccTLD Database.” Retrieved from https://lookup.icann.org/
2. Internet Assigned Numbers Authority. “Delegation Record for .GB.” Retrieved from https://www.iana.org/domains/root/db/gb.html
3. Zook, M. (2000). “Internet Metrics: using domain names to measure the growth and structure of the web.” Retrieved from https://onlinelibrary.wiley.com/doi/pdf/10.1111/1467-9663.00106
4. 123 Reg, “What is a Top Level Domain (TLD)?” Retrieved from https://www.123-reg.co.uk/support/domains/what-is-a-top-level-domain-tld/
