Cloud computing — concepts, services & best practices

A friendly one-page guide to the cloud: what it is, core services (IaaS/PaaS/SaaS), advantages, and where to start.

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What is cloud computing?

Cloud computing delivers compute, storage, and networking over the internet so organisations don't have to own and maintain physical servers. It's pay-as-you-go and scales on demand.

On-demandScalableManaged

Core service models

IaaS
Virtual machines, storage, networking — you manage OS and apps.
PaaS
Platform for deploying apps; provider manages runtime.
SaaS
Ready-to-use software delivered over the web.

Benefits

  • Lower capital expenses
  • Elastic scaling
  • Global reach
  • Managed security & updates

Major cloud providers

AWS, Microsoft Azure, Google Cloud Platform, plus specialized players like DigitalOcean, Oracle Cloud, and Alibaba Cloud.

Getting started

  1. Create a free-tier account (AWS/Azure/GCP)
  2. Learn core services: compute, storage, databases, networking
  3. Try a simple app deployment and a managed database
  4. Explore IaC (Terraform/CloudFormation)

Security basics

Principles: least privilege, encryption at rest and transit, network segmentation, monitoring and patching. Use IAM correctly and enable MFA.

Quick reference

• VM: virtual machine for custom workloads
• Container: lightweight runtime for microservices
• Serverless: run functions without managing servers