gtlds
Guides to the namespace

Learn the
namespace.

Plain-language explainers for the machinery behind top-level domains, written to separate protocol facts, registry policy, and useful context.

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Start with the shape of the DNS namespace.

Understand what a gTLD is first, then learn who operates one and how registration, resolution, RDAP and DNSSEC fit around it.

01What is a gTLD? 02Registry vs registrar 03RDAP & DNSSEC
Reference library

9 guides

Everything in the current guide library.

FundamentalsStart with the actors and namespace model

What is a gTLD?

Where generic top-level domains sit in DNS, how they differ from labels below them, and what delegation actually means.

Fundamentals5 min

gTLD vs ccTLD

The practical difference between generic and country-code top-level domains, and why the distinction is about namespace classification.

Fundamentals6 min

Registry vs registrar

Who operates the TLD, who sells registrations, and where registrants fit into the domain-name registration chain.

Fundamentals7 min
DNS & protocolTechnical records and discovery mechanisms

What is RDAP?

How Registration Data Access Protocol discovery works, what bootstrap data does, and how RDAP differs from legacy WHOIS.

Protocol8 min

DNSSEC at the root

What a DS record in the root establishes, how the chain of trust continues into a TLD, and what a reference site can safely report.

DNS9 min

Internationalized domain names

A-labels, U-labels, Punycode and why an IDN TLD should be searchable in both its ASCII and native-script forms.

Protocol8 min
Registry & policyContractual categories without invented restrictions

Sponsored gTLDs

What the sponsored classification represents and why sponsorship should not be conflated with ICANN community or brand status.

Policy6 min

Brand gTLDs & Specification 13

How ICANN's Specification 13 marks qualifying brand TLDs and why that contractual attribute belongs beside, not inside, IANA type.

ICANN7 min

Community gTLDs & Specification 12

Where community registration policies live and why eligibility rules must come from the actual agreement rather than the TLD string.

ICANN8 min
Editorial rule

Explain the machinery. Don't invent the policy.

Guide content separates authoritative facts, deterministic technical interpretation, and editorial explanation. Registry eligibility, restrictions, ownership and purpose are only stated when a primary source supports them.

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