Cloud Computing is the on-demand delivery of IT resources — including storage, computing power, databases, networking, and software — over the internet. Instead of owning and maintaining physical data centers and servers, you can access technology services from a cloud provider on a pay-as-you-go basis.
Core Concepts
Service Models
| Model | Full Name | Description |
|---|---|---|
| IaaS | Infrastructure as a Service | Provides virtualized computing resources over the internet (e.g., AWS EC2, Azure VMs). |
| PaaS | Platform as a Service | Provides a platform for developers to build, run, and manage applications (e.g., Google App Engine). |
| SaaS | Software as a Service | Delivers software applications over the internet on a subscription basis (e.g., Gmail, Dropbox). |
Deployment Models
- Public Cloud — Resources are owned and operated by a third-party provider and delivered over the internet (e.g., AWS, Azure, GCP).
- Private Cloud — Resources are used exclusively by a single organization, either on-premises or hosted by a third party.
- Hybrid Cloud — A combination of public and private clouds, allowing data and applications to move between them.
- Multi-Cloud — Using services from multiple cloud providers to avoid vendor lock-in.
Cloud Architecture
A typical cloud architecture includes:
- Frontend — The client-side interface (web browser, mobile app).
- Backend — Cloud resources including servers, storage, and databases.
- Cloud-based Delivery — The network (internet) that connects frontend and backend.
- Network — The internet infrastructure that enables communication.
Key Benefits
- Cost Savings — Replace capital expenses with variable operational expenses.
- Scalability — Scale resources up or down based on demand.
- Speed — Provision resources in minutes, not weeks.
- Global Reach — Deploy applications in multiple regions worldwide.
- Security — Cloud providers invest heavily in security policies, technologies, and controls.
Common Use Cases
- Website and app hosting
- Data backup and disaster recovery
- Big data analytics
- AI and machine learning workloads
- DevOps and CI/CD pipelines
- IoT data processing
Getting Started
To start with cloud computing, choose a provider that fits your needs:
- AWS — Largest ecosystem, best for enterprise and DevOps.
- Google Cloud — Best for AI/ML and data analytics.
- Azure — Best for organizations already using Microsoft products.
Most providers offer a free tier to explore services without upfront cost.
For an in-depth reference document covering architecture diagrams, advanced service comparisons, and cloud design patterns, refer to the full Cloud Computing guide.