What is an Azure region?

An Azure region is a geographical area containing one or more data centers, which are interconnected through a low-latency network.

Stay with me,

it's basically an area around the world where Microsoft has data centers. Think of it as a city block, but instead of houses, there are big, powerful buildings filled with servers and other techy stuff that run cloud services. They are designed to be readily available for you when you need them, they are reliable , and scalable by distributing resources across multiple data centers.

what is an Availability Zone?

An Availability Zone is a distinct location within an Azure region. it is designed to be isolated from failures in other Availability Zones within the same region. in essence, an Availability Zone is a location in your region.

Lets make an example

Consider running an online store. Without Availability Zones, it’s like having all your resources in a single warehouse. If that warehouse faces an issue, your entire store could be affected. But, With Availability Zones, it’s similar to having multiple warehouses in different parts of the city. If one warehouse encounters a problem, the others can continue to operate normally, minimizing any impact on your customers.

Deleting a Resource Group

when should I delete a resource group?
Delete a resource group when it is no longer needed or to clean up unused resources. Its part of Azure best practices. if you do no longer need a resource that is running why not delete it to save you cost?