Domain industry glossary

Plain-language definitions of the terms used in our reviews and methodology. Each entry has a stable anchor so we can link to it from other pages (e.g. methodology) and so search engines and AI agents can extract definitions cleanly.

Last updated 2026-05-12Prices checked monthlyHands-on testedTransparent methodology

60-day transfer lock#: An ICANN policy that prevents a gTLD domain from being transferred to a different registrar within 60 days of a new registration, a previous transfer, or a registrant contact change. Owners can transfer-out earlier if they explicitly opt out at registration time (where supported).
Auto-renew grace period#: The 45-day window after an expiration during which the registrar can return an auto-renewed domain to the registry for a refund. This is what enables most registrars to offer a 'free recovery within 45 days' policy on expired domains.
ccTLDcountry-code top-level domain#: A two-letter TLD assigned to a country or territory, such as .uk, .de, .ca, .il, .ai. ccTLDs are governed by their country's chosen registry and may have local-presence rules, language requirements, or restricted second-level domains.
DNSDomain Name System#: The hierarchical naming system that translates human-readable domain names into IP addresses and other resource records. A registrar's DNS quality is judged on supported record types, propagation behavior, and reliability of its authoritative servers.
DNSSECDomain Name System Security Extensions#: A set of extensions that cryptographically sign DNS records so resolvers can verify they haven't been tampered with. Registries publish DS records into the parent zone; the registrar typically provides a UI to upload your DS record.
EPP authorization codeauth code, transfer code#: A short alphanumeric code generated by the current registrar that the new registrar requires to initiate a transfer. The registrant must request it from the losing registrar; it cannot be obtained any other way.
Glue record#: An IP address record stored at the parent registry for a name server whose hostname falls under the same domain it serves. Used to break the chicken-and-egg lookup problem when ns1.example.com is the name server for example.com.
gTLDgeneric top-level domain#: A TLD not tied to a country, such as .com, .org, .net, .app, .dev. Most gTLDs are policy-governed by ICANN and have published wholesale price agreements.
IANAInternet Assigned Numbers Authority#: The function within ICANN that maintains the authoritative root zone file, the registry of all top-level domains, and global IP address allocation. The IANA root database lists the registry operator for every TLD.
ICANNInternet Corporation for Assigned Names and Numbers#: The non-profit organization that coordinates the assignment of domain names and IP addresses globally. ICANN accredits registrars, sets policy for generic top-level domains (gTLDs), and oversees the contractual relationships between registries and registrars.
ICANN fee#: A $0.18 USD per-year fee that ICANN charges registrars for each gTLD registration. It is itemized separately by some registrars (notably Cloudflare's at-cost pricing) and bundled into the headline price by others.
IDNInternationalized Domain Name#: A domain containing non-ASCII characters (e.g. Cyrillic, Hebrew, Chinese). Implemented via Punycode encoding in the DNS layer (xn--prefixed labels). Not all TLDs support IDNs.
Name servers#: The authoritative DNS servers a registrar configures at the registry to delegate a domain. Changing name servers points the domain to a different DNS provider (e.g. moving from your registrar's DNS to Cloudflare DNS) without transferring the domain itself.
Premium domain#: A domain reserved by the registry (or a previous registrant) and sold at a higher-than-standard wholesale price. Each registrar surfaces premium prices differently; some registrars don't sell premium tiers at all.
RDAPRegistration Data Access Protocol#: The structured JSON successor to WHOIS. ICANN required gTLD registries and registrars to support RDAP by 2019. RDAP supports standardized authentication, internationalized data, and machine-readable responses.
Redemption period#: The 30-day window after a gTLD domain expires during which the registrant can recover it by paying a redemption fee (typically $80-$200). After redemption, the domain enters a pending-delete state for 5 days, then drops to the open market.
Registrant#: The person or organization that legally owns a domain registration. Contact details for the registrant are recorded in the registry's WHOIS database (subject to privacy redaction).
Registrar#: An ICANN-accredited (for gTLDs) or registry-accredited (for ccTLDs) company that sells domain registrations to end users on behalf of registries. Registrars handle billing, DNS configuration, WHOIS records, and transfers.
Registrar lock#: A status flag (clientTransferProhibited) the registrar sets on a domain to block transfer requests until the registrant unlocks it. Helps prevent unauthorized transfers. Distinct from registry lock, which is set at the registry level for additional security.
Registry#: The organization that operates a top-level domain and maintains the master database of all second-level registrations under it. Examples: Verisign operates .com and .net; Public Interest Registry operates .org; Identity Digital operates .io.
Registry lock#: A higher-security lock applied at the registry, requiring out-of-band verification (often a phone call) before any change to the domain. Typically only offered for high-value domains and at a premium.
WHOIS#: A public directory protocol that returns ownership and contact information for a domain. Since the EU's GDPR took effect in 2018, registrant personal data is usually redacted in WHOIS output; registries and registrars retain the full records.
WHOIS privacy#: A service where the registrar substitutes its own proxy contact details for the registrant's personal data in WHOIS queries. Free WHOIS privacy is now standard at most major registrars on gTLDs and many ccTLDs.
Wholesale price#: The price the registry charges registrars per year for a domain registration or renewal. ICANN-governed gTLDs have published wholesale prices; ccTLD wholesale prices are set by the country registry. Cloudflare Registrar's 'at cost' model means they charge wholesale + ICANN fee with no markup.

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