A Web Address or Domain ends in a few letters that indicate where the web address belongs, similar to a post code or country code in an traditional postal mail address.

.COM - Managed internationally and does not require an ABN

.COM.AU - Australian Company or Business - Managed in Australia, and requires and ABN to register.

.INFO - Managed internationally and may not relate to a business.

 What is a domain Name?

A domain name is an identification label that defines a realm of administrative autonomy, authority, or control on the Internet, based on the Domain Name System (DNS).

Domain names are used in various networking contexts and application-specific naming and addressing purposes. They are organized in subordinate levels (subdomains) of the DNS root domain, which is nameless. The first-level set of domain names are the top-level domains (TLDs), including the generic top-level domains (gTLDs), such as the prominent domains com, net and org, and the country code top-level domains (ccTLDs). Below these top-level domains in the DNS hierarchy are the second-level and third-level domain names that are typically open for reservation by end-users that wish to connect local area networks to the Internet, run web sites, or create other publicly accessible Internet resources.

Individual Internet host computers use domain names as host identifiers, or hostnames. Hostnames are the leaf labels in the domain name system usually without further subordinate domain name space. Hostnames appear as a component in Uniform Resource Locators (URLs) for Internet resources such as web sites (e.g., en.wikipedia.org).

Domain names are also used as simple identification labels to indicate ownership or control of a resource. Such examples are the realm identifiers used in the Session Initiation Protocol (SIP), the DomainKeys used to verify DNS domains in e-mail systems, and in many other Uniform Resource Identifiers (URIs).