What actually sits between a visitor's browser and your application: the layers of compute, network, storage and operations that make up modern cloud hosting.
A typical path for a single web request, from the user to the app and back.
Every hosting platform, from a single VPS to a hyperscaler, is made of the same core pieces.
Virtual machines, containers and serverless functions that run your code. Sized by CPU, memory and GPU.
Virtual private networks, public IPs, load balancers and firewalls that route and filter traffic.
Block disks for servers, object storage for files and backups, and managed databases for structured data.
Caches content close to users worldwide to cut latency and absorb traffic spikes and attacks.
TLS certificates, identity and access management, intrusion protection, encryption at rest and in transit.
Metrics, logs, traces and alerts so you know when something is slow or broken — before your users do.
How much of the stack you manage yourself versus the provider.
| Model | You manage | Provider manages | Examples |
|---|---|---|---|
| VPS / IaaS | OS, runtime, app, data | Hardware, virtualization, network | Virtual servers, bare metal |
| PaaS | App and data | OS, runtime, scaling | App platforms, managed containers |
| Serverless | Functions and data | Everything else, billed per request | Functions, edge workers |
| SaaS | Configuration and content | The whole application | Hosted CMS, email, CRM |
Principles that keep a hosted service up when individual parts fail.
Run at least two of everything critical, across separate availability zones.
Add more instances behind a load balancer instead of buying one bigger server.
Automated, off-site, and regularly tested restores. A backup you haven't restored is a guess.
Define servers and networks in version-controlled files so environments are reproducible.