What Is Cloud Computing and AWS?
Understand the difference between on-premises, IaaS, PaaS, and SaaS, and see how AWS fits into each model.
What Is Cloud Computing and AWS? is a free AWS Solutions Architect lesson on CoddyKit — lesson 1 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the AWS Solutions Architect learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
What Is Cloud Computing?
Cloud computing lets you rent servers, storage, and databases over the internet and pay only for what you use — no buying or running your own data centre.
On-Premises vs Cloud
On-premises, you own and run all the hardware. In the cloud you spin up resources in minutes and stop paying when you're done. That's agility, elasticity, and reach.
IaaS: Infrastructure as a Service
IaaS hands you raw building blocks — virtual machines, networking, storage. You manage the OS and apps; AWS handles the hardware. EC2 is the classic example.
# Example: launching a basic EC2 instance via AWS CLI (IaaS)
aws ec2 run-instances \
--image-id ami-0abcdef1234567890 \
--instance-type t3.micro \
--key-name MyKeyPair \
--subnet-id subnet-12345678PaaS: Platform as a Service
PaaS hides the infrastructure so you just ship code. AWS handles patching and scaling — Elastic Beanstalk sets up servers and load balancers for you automatically.
# Deploy an app with Elastic Beanstalk (PaaS)
eb init my-app --platform node.js --region us-east-1
eb create my-env
eb deploySaaS: Software as a Service
SaaS is ready-to-use software over the internet — nothing to manage underneath. Think Gmail or Salesforce; you just log in and use it.
Who Is Amazon Web Services?
AWS launched in 2006 and is the world's most widely used cloud, with 200+ services and data centres worldwide. It's the platform the SAA-C03 exam is built on.
Key Cloud Benefits: Elasticity
Elasticity means resources grow and shrink with demand. Auto Scaling adds servers during a rush and removes them when it's quiet, so you pay only for what you use.
Key Cloud Benefits: Agility and Speed
Agility means launching a server, database, or global CDN in minutes instead of weeks. You can experiment cheaply, fail fast, and reach the market sooner.
CapEx vs OpEx in Cloud Economics
Traditional IT means big upfront spending — CapEx. The cloud turns that into pay-as-you-go OpEx, so your costs line up directly with what you actually use.
Deployment Models: Public, Private, Hybrid
There are three cloud models: public (shared AWS), private (dedicated to one org), and hybrid (a mix). Most enterprises run hybrid, especially while migrating.
AWS Pricing Principles
AWS pricing follows three ideas: pay as you go, pay less when you reserve ahead, and pay less as your volume grows. These power most cost-optimisation questions.
Quick Check
Test your understanding of AWS Solutions Architect (SAA-C03) concepts from this lesson.
Lesson Recap
You learned the cloud delivers IT on demand, that IaaS, PaaS, and SaaS mean less and less for you to manage, and that AWS turns CapEx into OpEx. Next: global infrastructure.
Frequently asked questions
Is the “What Is Cloud Computing and AWS?” lesson free?
Yes — the full text of “What Is Cloud Computing and AWS?” is free to read here on the web, and the AWS Solutions Architect course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the AWS Solutions Architect course, upgrade to CoddyKit PRO.
What will I learn in “What Is Cloud Computing and AWS?”?
Understand the difference between on-premises, IaaS, PaaS, and SaaS, and see how AWS fits into each model. You practise AWS Solutions Architect with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start AWS Solutions Architect?
No prior experience is required. AWS Solutions Architect on CoddyKit is structured for beginners through advanced learners; this is — lesson 1 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “What Is Cloud Computing and AWS?” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this AWS Solutions Architect lesson?
Yes. Every AWS Solutions Architect lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- What Is Cloud Computing and AWS?
- AWS Global Infrastructure
- Core Service Categories Overview
- Shared Responsibility Model