DepthSurface
Layer 3 · Software as a Service

You just open it.

Gmail, Drive, Salesforce. You sign in and use it — nothing to install, patch, or host. The entire stack underneath is someone else's job.

You manageProvider manages
Your data & loginsEverything else
Layer 2 · Platform as a Service

Bring code. They run it.

Beneath the app sits a managed platform — runtime, libraries, scaling, load-balancing. You push code; the platform decides where and how it runs.

You manageProvider manages
Your code & dataRuntime, OS, servers, scaling
Zoom in · One server, one VM

Your app is one process, on one box.

That whole platform runs inside a single virtual machine — a rented slice of one physical server. The other slices belong to other tenants. This slice is the unit IaaS actually sells.

node-074 vCPU16 GB RAMUbuntu 22.04app.py · running
Layer 1 · Infrastructure as a Service

It's real metal, in a real building.

Strip everything away and you hit the floor: racks of physical servers, power, cooling, network — someone on call at 3am. IaaS rents you slices of this. You own the OS and up.

You manageProvider manages
OS, runtime, app, dataServers, storage, network, building
The whole stack · one building

And it's somewhere real.

Every app you opened today lives in places like this — halls of servers drawing megawatts, cooled day and night, wired to the world. The cloud is just someone else's computers, in a building, on the ground.

thousands of servers24/7 power & coolingfibre to the planet
SaaSThe app
PaaSThe platform
IaaSThe hardware
You reached the bottom of the cloud · scroll up to climb back out