Terminology

Term	Description
Registry	The core contract at the heart of ENS that all lookups start from.
Registrar	A contract that owns a name and issues subnames for it.
.eth Registrar:	The owner of the eth name. This contract issues .eth second-level names (like name.eth) in the form of an ERC-721 NFT.
Owner	The owner of a .eth second-level name. If the Owner is transferred to another account, then you lose ownership of the name.
Manager	The account that can edit records for an ENS name.
Resolver	A contract that determines how your ENS name "resolves" or "points to" records such as an ETH address. Usually this is done by storing the records on-chain.
Expiration Date	The date and time at which a .eth ENS name expires. If you want to keep the name, then renew it before it expires.
Grace Period	This is a short window of time after an ENS name expires, in which the owner can still renew and retain the name. Currently this window is 90 days.
Temporary Premium Auction	After a name's grace period ends, it gets automatically released into a public Dutch auction where a temporary premium is applied.
Primary Name	The ENS name that you want a particular ETH account to be associated with. When set, it will be displayed instead of your 0x address on integrating websites/apps.
Name	This is a generic term for any individual ENS name. This can include a .eth second-level name like name.eth, DNS names like name.xyz, or even subnames like sub.name.eth.
Subname	A child name like sub.name.eth, whose parent is name.eth. Also referred to as a "subdomain". Every name (except for the root node) has a parent. For example, name.eth is a subname of eth.
TLD	Top-level domain. This refers to names like eth, com, xyz which lie at the "top" of the naming hierarchy.
2LD	Second-level domain. This refers to a subname/subdomain of a top-level domain. For example, name.eth and name.com are both second-level names.
Record	A piece of information that an ENS name "resolves" to (points to). The most common record is the ETH Address record, which determines what ETH 0x address an ENS name points to.
Text Record	This is a record that maps an ENS name to a particular text value. For example, you can use the description text record to set a description for your ENS name that can be displayed to the world (like a profile bio).
Avatar	This is a text record that sets an image or "avatar" for your ENS name.
Content hash	This record links your ENS name to a decentralized website. Supporting browsers can then resolve and load that website directly from your ENS name.