Putting this together with things I already know

Geography = Australia

For Geography I like to think of a Country

Regions

• Australia East = Brisbane
• Australia Central = Sydney
• Australia Central 2 = Canberra
• Australia Southeast = Melbourne

Within Azure I think that Regions loosely equate to Locations. Looking at the output of Get-AzLocation as shown below

Availability Zones would be separate data centers in a Region e.g they need to be close to each other so the latency is low. Microsoft doesn't have many Availability Zone enabled regions in comparison to AWS. For example there may be 3 data centers in a city that Microsoft groups into an Availability Zone

The next level down as I see it is Fault Domains and Update Domains. AKA Availability Sets. Apparently it helps to think of them as follows

• Fault Domain - Server Rack (separate power and hardware) with a bunch of servers in it
• Update Domain - Individual servers that get updated and patched at different times than other servers in the same rack

Apparently there are different numbers of Fault Domains available in different regions but the default is 3

Regions are also paired to allow BCDR practices within a Geography (i.e. you don't send your data overseas but the paired region is far enough away hopefully not to suffer an outage too)

For Australia the pairings are

Geography	Region/Location	Region/Location
Australia	Australia East	Australia Southeast
Australia	Australia Central	Australia Central 2