When I started learning AWS, I quickly realized one thing: before jumping into services like EC2 or S3, I first needed to understand the basics of cloud.

So on Day 1, I focused on four things:

How AWS pricing works
What on-premises, cloud, and hybrid mean
The difference between IaaS, PaaS, and SaaS
A quick look at AWS history

Let me explain these in simple words.

💰 AWS Pricing Models – How You Pay

The cool thing about AWS is you don’t buy big servers upfront. Instead, you pay only for what you use. Here are the options:

On-Demand → Pay as you go. No commitment. Best for learning or testing.
Reserved → Commit for 1–3 years, get big discounts. Best for things running 24/7 (like a website).
Spot → Super cheap but AWS can take it back anytime. Best for short, flexible tasks.
Savings Plans → Like Reserved, but more flexible.

👉 Think of it like traveling:

On-Demand = Taxi (pay for the ride).
Reserved = Own a car (long-term use).
Spot = Carpool (cheap, but not always available).
Savings Plan = Monthly bus pass (save money if you travel often).

☁️ On-Premises, Cloud, and Hybrid

Here’s how companies use servers:

On-Premises → Servers in your own office/data center. More control, but expensive.
Cloud → Rent servers from AWS or others. Flexible, cheaper, and no maintenance.
Hybrid → A mix of both.

👉 Imagine storing your stuff:

On-Premises = Keeping everything at home.
Cloud = Renting storage space.
Hybrid = Keep some things at home, rest in storage.

⚙️ IaaS, PaaS, SaaS – The Three Service Models

These are just fancy names for how much of the work you want AWS to handle:

IaaS (Infrastructure as a Service) → You rent servers, storage, networks. Example: EC2.
PaaS (Platform as a Service) → AWS gives you a ready platform to run apps. Example: Elastic Beanstalk.
SaaS (Software as a Service) → You just use the software. Example: Gmail, Zoom.

👉 Think of food:

IaaS = Buy ingredients, cook yourself.
PaaS = Get a meal kit, just follow steps.
SaaS = Order a pizza, just eat.

📖 A Quick AWS History

2006 → AWS started with EC2 and S3.
2012 → Free Tier launched → anyone could try AWS.
Today → AWS has 200+ services and is the biggest cloud provider.

✅ Wrap-Up

On Day 1, I learned that:

AWS pricing is flexible and depends on your needs.
Cloud models = On-premises (own it), Cloud (rent it), Hybrid (mix).
IaaS, PaaS, SaaS are just levels of control.
AWS started small but now powers companies worldwide.

This foundation helped me see AWS in a much clearer way. Instead of random services, I now understand the “why” behind the cloud.

AWS Fundamentals for Beginners: Pricing, Cloud Models, and IaaS/PaaS/SaaS