Stop 01 · Cloud Computing FoundationsTopics · 4/9

Public, Private & Hybrid Cloud

In short

When someone says 'we're on the cloud', ask which kind. A startup on AWS, a bank with its own private cloud, and a hospital using both have very different setups and problems.

Public cloud is shared infrastructure run by a provider (AWS, Azure, GCP), private cloud is dedicated infrastructure for one organization, and hybrid cloud combines both — often driven by compliance or existing infrastructure investment.

The blob character drives a small car up to a train waiting at a station platform.

Think of it like this

Train, own car, or both

A train is public: shared coaches, cheap, runs on someone else's schedule. Your own car is private: only you, costly, fully in your control. Driving to the station and then taking the train is hybrid.

Watch it happen

Three ways to run a cloud

Cloud models

Public

Shared hardware

Private

One organisation

Hybrid

On-prem + public

Linked by VPN

1/4Every cloud gives self-service, on-demand resources. The difference is who shares the hardware.

The big ideas

What you need to know

Public is shared

You rent from a provider alongside thousands of other customers. Fastest to start, widest range of services.

Private is dedicated

Hardware for one organisation, run by them or a vendor. More control, but you pay for capacity even when idle.

Hybrid mixes both

Common when old systems can't move yet, or rules say some data must stay in your own building.

Multi-cloud is different

Multi-cloud means using more than one public provider. Hybrid means mixing on-premise with cloud. People confuse the two.

Save yourself the pain

Common mistakes

Oops

Thinking public cloud means your data is visible to the public.

Do this instead

'Public' means the hardware is shared among customers. Your resources are private to your account unless you open them up.

Oops

Calling any company with two clouds 'hybrid'.

Do this instead

Two public providers is multi-cloud. Hybrid specifically joins your own on-premise setup with a cloud.

Your mission

Classify real setups

~20 min

Quick check

A hospital keeps patient records in its own data centre but runs its appointment website on Azure. What is this?

Go deeper

1List a legitimate reason a company might need private or hybrid cloud despite public cloud's convenience.
2Learn why regulated industries (banking, healthcare) often require hybrid setups.
3Understand most job postings in this field assume public cloud skills as the baseline.