# What is Cloud Computing? — AWS

Source: https://www.geekswithgeeks.com/en/aws/aws-cloud-computing

> Renting compute, storage, and networking instead of owning hardware.

## The core idea

Cloud computing means renting **compute, storage, and networking** from a provider over the internet, paying only for what you use, instead of buying and maintaining your own servers.

## IaaS, PaaS, SaaS at a glance

**IaaS** gives raw building blocks — servers, storage, networks (e.g. EC2). **PaaS** manages the runtime for you, you just deploy code (e.g. Elastic Beanstalk). **SaaS** is a finished application you simply use (e.g. Gmail). AWS mostly sits at IaaS/PaaS.

## Electricity, not a generator

Before the grid, every factory ran its own generator. The cloud is like the electricity grid: you plug in and pay per unit used, instead of owning, maintaining, and over-sizing your own power plant.

## Pay-as-you-go mindset

Think in **usage**, not capacity you pre-bought. Scale up during load, scale down after — the whole point of the cloud is not paying for idle hardware.