Cloud - Concept
Availability zone
A separate cloud location designed so a failure there does not affect neighbouring locations
What's it for?
Lets organisations spread important systems across separate locations so one local failure does not stop everything.
For example…
The e-commerce checkout runs in three availability zones; if one zone loses power, shoppers still pay
A service runs in two availability zones so maintenance or a power problem in one site does not take it offline.
Think of it like…
Having kitchens in different wings of a hotel — a fire in one wing need not stop every meal