Editing Domain name (section)

===Domain name syntax===
A domain name consists of one or more parts, technically called ''labels'', that are conventionally concatenated, and delimited by dots, such as ''[[example.com]]''.
* The right-most label conveys the [[top-level domain]]; for example, the domain name ''www.example.com'' belongs to the top-level domain ''com''.
* The hierarchy of domains descends from the right to the left label in the name; each label to the left specifies a subdivision, or [[subdomain]] of the domain to the right. For example: the label ''example'' specifies a node ''example.com'' as a subdomain of the ''com'' domain, and ''www'' is a label to create ''www.example.com'', a subdomain of ''example.com''. Each label may contain from 1 to 63 [[octet (computing)|octets]]. The empty label is reserved for the root node and when fully qualified is expressed as the empty label terminated by a [[full stop|dot]]. The full domain name may not exceed a total length of 253 ASCII characters in its textual representation.<ref name="rfc1035">{{cite journal |title=Domain names - Implementation and specification (RFC 1035) |last=Mockapetris |first=P. |date=November 1987 |url=https://datatracker.ietf.org/doc/rfc1035/ |website=IETF Datatracker |access-date=January 21, 2024}}</ref>
* A [[hostname]] is a domain name that has at least one associated IP address. For example, the domain names ''www.example.com'' and ''example.com'' are also hostnames, whereas the ''com'' domain is not. However, other top-level domains, particularly [[country code top-level domain]]s, may indeed have an IP address, and if so, they are also hostnames.
* Hostnames impose restrictions on the characters allowed in the corresponding domain name. A valid hostname is also a valid domain name, but a valid domain name may not necessarily be valid as a hostname.