Austpost.com.au/mail extension

The .au top-level domain (TLD) is the country-code TLD for Australia, and austpost.com.au is a domain name registered by Australia Post, the national postal service of Australia.

The mail extension is a subdomain of austpost.com.au, which is used to provide email services to customers. The full domain name is mail.austpost.com.au.

Here's a breakdown of the domain name:

• austpost.com.au: The main domain name registered by Australia Post, which represents their online presence.
• mail: A subdomain of austpost.com.au, which is used to provide email services to customers.
• .com.au: The country-code TLD for Australia, indicating that the domain is registered in Australia.

So, mail.austpost.com.au is an email service provided by Australia Post, allowing customers to access their email accounts online.