Cloud Concepts Overview
The six advantages of cloud computing, service and deployment models — the foundational concepts for every AWS exam
What is Cloud Computing?
Cloud computing is the on-demand delivery of IT resources (compute power, database, storage, applications, and more) via the internet with pay-as-you-go pricing. These resources run on server computers in large data centers located in different locations around the world.
Cloud computing enables you to stop thinking of infrastructure as hardware, and instead think of it as software. Software solutions are flexible, can change quickly and cost-effectively, and eliminate undifferentiated heavy-lifting tasks like procurement, maintenance, and capacity planning.
Traditional Computing vs. Cloud Computing
| Traditional (Hardware) | Cloud (Software) |
|---|---|
| Requires space, staff, physical security, planning, capital expenditure | No upfront investment — on-demand provisioning |
| Long hardware procurement cycles (weeks to months) | Resources available in minutes |
| Provision capacity by guessing theoretical maximum peaks | Scale up/down elastically based on actual demand |
| Over-provision → pay for idle resources. Under-provision → insufficient capacity | Pay only for what you use, when you use it |
| Changes require time, effort, and money for new hardware | Treat resources as temporary and disposable |
The Six Advantages of Cloud Computing
These are the most frequently tested cloud concepts on the exam. Every question about "why move to the cloud" maps back to one or more of these advantages:
| # | Advantage | What It Means |
|---|---|---|
| 1 | Trade capital expense for variable expense | No huge upfront data center investments. Pay only when you consume, and pay only for the amount you consume. CapEx → OpEx shift. |
| 2 | Benefit from massive economies of scale | AWS aggregates usage from hundreds of thousands of customers. The resulting economies of scale translate into lower pay-as-you-go prices for you. |
| 3 | Stop guessing capacity | No more over-provisioning (waste) or under-provisioning (downtime). Access exactly what you need, scale up/down as needed with only minutes' notice. |
| 4 | Increase speed and agility | New IT resources are a click away — reduce availability time from weeks to minutes. Lower cost/time to experiment fuels faster innovation. |
| 5 | Stop spending money on running and maintaining data centers | Focus on projects that differentiate your business, not the heavy lifting of racking, stacking, and powering servers. |
| 6 | Go global in minutes | Deploy in multiple AWS Regions with a few clicks. Provide lower latency and better experience for customers globally at minimal cost. |
Cloud Service Models
Three models represent different parts of the cloud computing stack — each gives a different level of control:
| Model | You Manage | Provider Manages | Examples |
|---|---|---|---|
| IaaS | Applications, data, runtime, middleware, OS | Virtualization, servers, storage, networking | Amazon EC2, EBS, VPC |
| PaaS | Applications, data | Runtime, middleware, OS, virtualization, servers, storage, networking | AWS Lambda, RDS, Elastic Beanstalk |
| SaaS | Usage configuration, data input | Everything else — complete product | Trusted Advisor, Shield, Chime, web-based email |
Cloud Deployment Models
Three models for how your applications can be deployed:
| Model | Description |
|---|---|
| Cloud (All-in) | Fully deployed in the cloud. Created in the cloud or migrated. Take advantage of all cloud benefits. Can use low-level or high-level services. |
| Hybrid | Connects cloud-based resources with existing on-premises infrastructure. Extend and grow into the cloud while connecting to internal systems. Most common method of initial migration. |
| On-Premises (Private Cloud) | Resources deployed on-premises using virtualization and resource management tools. Does not provide most cloud benefits. Sometimes chosen for dedicated resources. Similar to legacy IT with virtualization for better utilization. |
Three Ways to Interact with AWS
| Method | Description | Best For |
|---|---|---|
| AWS Management Console | Rich graphical interface; access to most features | Learning, simple tasks, visual monitoring |
| AWS CLI | Command-line utilities; scriptable | Automation, scripting, DevOps workflows |
| AWS SDKs | Language-specific packages (Java, Python, .NET, etc.) | Embedding AWS calls in application code |
All three are built on a common REST-like API. Choose based on your workflow — they access the same backend services.
Cloud Concepts Quiz
Select one answer per question. You will receive immediate feedback.