# AWS Core Services

The AWS console lists hundreds of services, and that wall of three-letter names is enough to make anyone close the tab. Here's the secret nobody puts on the front page: most real applications run on about five of them. Learn those five and how they snap together, and the other several hundred become "things I'll look up if I ever need them" instead of "things I'm failing to understand."

This guide hands you the small, durable core - object storage, virtual machines, managed databases, the permission model, and serverless functions - plus the one mental model (who-can-do-what) that everything else hangs from.

## How to read this

Read the phases in order; they build. Phase 1 gives you the map and the names so the rest stops feeling like alphabet soup. Phase 2 wires the five services into the shape of a real app, which is where it clicks. Phase 3 is the part that saves your weekend: the IAM permission model and the mistakes that page people at 3am.

You don't need an AWS account open to follow along - every command is annotated so you can read it like prose. If you want broader context on what "cloud" even means first, see [/guides/cloud-platforms-explained](/guides/cloud-platforms-explained).

## The phases

1. [The five services that matter](01-the-five-that-matter.md) - the mental model and what each core service actually does.
2. [Wiring them into an app](02-wiring-an-app.md) - how S3, EC2, RDS, IAM, and Lambda fit together in a typical stack.
3. [IAM, least privilege, and what bites you](03-iam-and-what-bites-you.md) - the permission model in depth, plus the production gotchas.