Fake email glossary: MX record, DNS, punycode and other terms
Our articles use the real names of things — the same names you will see in your domain's control panel, in error messages and in documentation. That way you can find the right setting or look the word up. When a term is unclear, click it in any article and you land here, on its short explanation.
Domains
Domain zone (TLD)
The last part of a domain name: .com, .net, .de, .email. TLD stands for top-level domain. Each zone has its own rules and its own reputation, which affects whether sign-up forms accept addresses from it. See: choosing a domain for fake email.
Subdomain
A name inside another domain: mail.example.com is a subdomain of example.com. It belongs to whoever owns the main domain, so it depends on two owners instead of one.
Wildcard domain
A domain set up so that any subdomain works: anything.example.com, other.example.com and so on all receive mail without being created one by one.
Registrar
The company you buy a domain from and where you manage it: you pay it, and in its control panel you change the domain's DNS records. See: free domain registrars for fake email.
Registry
The organisation that runs a whole zone (for example, all .com names) and keeps the master list of its domains. You do not deal with it directly — the registrar does.
ICANN
The international body that coordinates domain names. It accredits registrars and sets the rules most zones follow, including how expired domains are handled.
WHOIS
A public lookup that shows who registered a domain, through which registrar, and when it expires. Privacy services can hide the owner's contact details from it.
Domain status (registry status)
A code the registry puts on a domain to show its state: ok for normal, clientHold or serverHold when it is switched off, redemptionPeriod after it expired but can still be bought back, and pendingDelete just before it is released. See: fake email domain stopped working.
DNS
DNS
The Domain Name System — the internet's address book. It answers questions like “which server handles mail for this domain?”. Without working DNS a domain cannot receive anything.
Name server (NS)
The server that holds a domain's DNS records and answers questions about them. If a domain has no name servers, the internet cannot find anything about it — it is effectively switched off. See: fake email domain debugger.
DNS record
One line of settings for a domain, such as “mail goes to this server”. Records have a type (MX, A, CNAME, TXT, NS…), a value and a TTL. You add and edit them at your registrar.
MX record
The DNS record that says which server receives mail for a domain (MX means mail exchanger). It is the one record you add to receive fake email at your own domain. See: add a new fake email domain.
A record
The DNS record that points a name to an IP address — usually where a website lives. It does not route mail; for mail you need an MX record.
CNAME record
A DNS record that says “this name is an alias of that other name”. It cannot replace an MX record for receiving mail.
TXT record
A DNS record that holds free text, often used to prove you own a domain or to describe mail rules. It does not route mail.
NS record
The DNS record that lists a domain's name servers.
SOA record
The DNS record with a domain's basic technical details (its main name server and timing settings). It exists for every working domain.
TTL
Time to live: how many seconds other servers may remember a DNS record before asking again. It is why a change can take a while to be seen everywhere.
Mail delivery
SMTP
The standard way mail servers pass messages to each other. Every message that reaches a fake email inbox arrives by ordinary SMTP, like any other mail.
Greylisting
An anti-spam method: the receiving server asks an unknown sender to try again a few minutes later. Real senders retry, so the message arrives — just with a delay. See: receive verification codes with fake email.
Bounce
A message that could not be delivered and comes back to the sender with an error, for example because the domain does not accept mail.
Block-list
A list of domains or addresses a website refuses. Many sites keep lists of known fake email domains and reject them at sign-up. See: a site won't accept your fake email.
Email headers
The technical lines at the top of every message: who sent it, through which servers, when, and with what settings. Normally hidden by mail programs.
IP address
The number that identifies a device or connection on the internet. Every site you visit sees yours; it roughly shows your provider and region.
Addresses and names
Local part
Everything before the @ in an address — the name. The standard allows up to 64 characters. See: fake email generator FAQ.
Gmail dots and plus addresses
Gmail ignores dots in the name and anything after a +, so j.ohn+shop@gmail.com reaches the same mailbox as john@gmail.com. See: fake Gmail and Gmail Washer.
ASCII
The basic set of plain Latin letters, digits and symbols that mail servers were built on. Names outside it have to be converted before they travel.
Unicode
The standard that covers the letters of all languages and emoji. Domains written in Unicode are converted to ASCII (punycode) behind the scenes.
IDN (internationalised domain name)
A domain with non-Latin letters or emoji, like пошта.укр or 🎅.example. See: fake email on emoji domains.
Punycode
The way an IDN is written in plain ASCII: a code that starts with xn--. The same name always gives the same code, and it can be turned back. See: punycode converter.
For developers
API
A way for programs, rather than people, to use a service. This site has no public API. See: fake email for testing.
RFC
A numbered internet standard document. For example, RFC 2606 reserves example.com and similar names for documentation and tests.
localhost
The name a computer uses for itself. A link to localhost in a real message only works on the sender's own machine — for everyone else it is broken.