While the simplest explanation for a domain name may be "a unique name that identifies an internet resource such as a website," to convey the full spectrum of interlocking issues that govern and maintain them, it is useful to examine the data entities, DNS hierarchy, and objects that comprise the typical WHOIS records that describe them.
The basic, prerequisite knowledge of the overall domain name ecosystem includes individual domains and the data elements that describe them, their corresponding registries, which manage each domain's parent TLD, and the registrars, which provide the interface between our names and their registries.