Domain Name Glossary
Essential domain industry terms explained in plain English. Bookmark this page for quick reference.
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Auth Code (Authorization Code)
A secret code (also called an EPP code or transfer key) required to transfer a domain between registrars. The current registrar provides this code to the domain owner, who then shares it with the receiving registrar to authorize the transfer. Without the auth code, a domain transfer cannot proceed.
WHOIS
A publicly accessible protocol and database that stores registration information about domain names. WHOIS records typically include the registrant's name, contact information, registration date, expiration date, and nameservers. Many domain owners use privacy protection services to mask their personal information in WHOIS records.
RDAP (Registration Data Access Protocol)
The modern replacement for the WHOIS protocol, providing a standardized way to access domain registration data. RDAP offers structured responses in JSON format, supports internationalized text, and provides differentiated access based on the requester's identity. It's gradually replacing WHOIS across the domain industry.
Registrar
A company accredited by ICANN (or a country-code registry) to sell domain name registrations to the public. Popular registrars include GoDaddy, Namecheap, Cloudflare, and Google Domains. Registrars are the intermediary between domain buyers and the registries that operate the TLDs.
Registry
The organization that operates and maintains a top-level domain (TLD). For example, Verisign operates the .com and .net registries, while the Public Interest Registry operates .org. Registries manage the authoritative database of all domain names within their TLD and set wholesale prices that registrars pay.
TLD (Top-Level Domain)
The last part of a domain name — the extension that comes after the final dot. Examples include .com, .org, .net, .io, and .ai. TLDs are divided into generic TLDs (gTLDs like .com), country-code TLDs (ccTLDs like .uk), and newer generic TLDs (.app, .dev, .tech).
ccTLD (Country Code Top-Level Domain)
A two-letter top-level domain assigned to a specific country or territory. Examples include .uk (United Kingdom), .de (Germany), .jp (Japan), and .io (British Indian Ocean Territory). Some ccTLDs like .io and .ai have been widely adopted beyond their geographic territory for their alternative meanings.
gTLD (Generic Top-Level Domain)
A top-level domain that is not tied to a specific country. Original gTLDs include .com, .net, .org, .edu, .gov, and .mil. Since 2012, ICANN has approved hundreds of new gTLDs including .app, .dev, .tech, .shop, and many more. These newer extensions are sometimes called "new gTLDs" or "ngTLDs."
Domain Parking
The practice of registering a domain name and displaying placeholder content — usually pay-per-click advertisements — instead of developing a full website. Domain parking generates passive income from type-in traffic (visitors who type the domain directly into their browser). Services like Sedo and ParkingCrew provide parking pages.
Domain Flipping
The practice of buying domain names at a low price and reselling them at a higher price for profit. Similar to flipping real estate, domain flipping requires identifying undervalued domains, purchasing them, and finding buyers willing to pay more. The profit margin varies wildly — from a few dollars to hundreds of thousands.
Drop Catching
The practice of using automated systems to register a domain name the instant it becomes available after expiration. Services like SnapNames, DropCatch, and NameJet specialize in drop catching, using networks of registrar accounts to submit registration requests simultaneously. For popular domains, multiple services compete, and the domain typically goes to auction.
Backorder
A request placed with a drop-catching service to attempt to register a specific domain name when it becomes available after expiration. Backorders are placed in advance and the service will try to catch the domain on your behalf. If multiple backorders exist for the same domain, it typically goes to auction among the backorder holders.
Grace Period
The window after a domain expires during which the original registrant can renew it at the standard renewal price. Grace periods typically last 0-45 days depending on the registrar and TLD. During this period, the domain may stop resolving but the original owner retains priority to renew it without additional fees.
Redemption Period
A 30-day period that follows the grace period, during which the expired domain can still be recovered by the original owner — but at a significantly higher cost (typically $80-200+ in addition to the renewal fee). The redemption period is the last chance to recover a domain before it's deleted and potentially dropped to the open market.
ICANN (Internet Corporation for Assigned Names and Numbers)
The nonprofit organization responsible for coordinating the maintenance and procedures of several databases related to the namespaces and numerical spaces of the Internet. ICANN oversees the domain name system (DNS), accredits domain registrars, and manages the introduction of new TLDs. Based in Los Angeles, it plays a central role in internet governance.
DNS (Domain Name System)
The internet's system for converting human-readable domain names (like notrenewing.com) into IP addresses (like 192.168.1.1) that computers use to identify each other. DNS is often called the "phonebook of the internet." When you type a domain name into your browser, DNS servers translate it to the correct IP address so your browser can load the website.
Nameserver
A server that stores DNS records and responds to queries about domain names. When you register a domain, you point it to nameservers that tell the internet where your website is hosted and where your email should be delivered. Common nameserver providers include Cloudflare, AWS Route 53, and your hosting company.
Domain Transfer
The process of moving a domain name from one registrar to another. Transfers require an authorization code from the current registrar, and typically take 5-7 days to complete. ICANN rules require that domains be at least 60 days old before they can be transferred, and domains cannot be transferred within 60 days of a previous transfer.
EPP Code
Another name for the authorization code (auth code) required to transfer a domain. EPP stands for Extensible Provisioning Protocol, the standard protocol used by registrars to communicate with domain registries. The EPP code is essentially a password that proves you have the right to move the domain.
Registrant
The person or organization that has registered a domain name. The registrant is the legal owner of the domain and has the right to use, sell, or transfer it. Registrant information is stored in the WHOIS/RDAP database, though privacy protection services can mask personal details from public view.
UDRP (Uniform Domain-Name Dispute-Resolution Policy)
An ICANN policy that provides a mechanism for trademark holders to resolve disputes over domain names. If a trademark owner believes a domain was registered in bad faith (cybersquatting), they can file a UDRP complaint. A panel of arbitrators decides whether the domain should be transferred to the complainant. Filing costs $1,500-5,000.
Cybersquatting
The practice of registering a domain name containing a trademark or brand name with the intent to profit from it — typically by selling it back to the trademark holder at an inflated price. Cybersquatting is prohibited under the Anticybersquatting Consumer Protection Act (ACPA) in the US and can be challenged through UDRP proceedings.
Brandable Domain
A domain name that works well as a brand name — typically short, easy to pronounce, easy to spell, and memorable. Brandable domains may be invented words (like "Spotify" or "Zapier"), compound words (like "Facebook"), or evocative names (like "Apple"). They're increasingly valued over exact-match keyword domains.
Exact Match Domain (EMD)
A domain name that exactly matches a search query, such as "cheapflights.com" for the search "cheap flights." EMDs were once extremely valuable for SEO because Google gave them ranking advantages, but this benefit has been significantly reduced since Google's 2012 EMD Update. They still carry some brand recognition value.
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