Cloud
AWS
Amazon Web Services — the largest cloud, with 200-plus services from compute (EC2, Lambda) and storage (S3) to databases, networking and ML. Its breadth and maturity make it the enterprise default. The flip side is sprawling complexity, IAM that is easy to misconfigure, and bills that surprise you without deliberate cost controls.
Purpose
Amazon Web Services is the largest public cloud: over two hundred services spanning compute (EC2 servers, Lambda functions), storage (S3), databases (RDS, DynamoDB), networking and machine learning, rentable by the hour or the request. It exists so teams can provision in minutes what once took a procurement cycle.
When to Use It
Everything from a static site on S3+CloudFront to global multi-region platforms. Its maturity — depth of services, compliance coverage, hiring pool — makes it the default enterprise choice and the lingua franca of cloud job postings.
Trade-offs
Breadth brings sprawl: overlapping services, a steep learning curve, and an IAM permission model that is powerful and notoriously easy to misconfigure. Costs surprise the undisciplined — egress fees, forgotten instances — so budgets, alerts and tagging are not optional.
Implementation
Start with the core: IAM (least-privilege roles, no root usage, MFA), VPC networking, EC2/ECS/Lambda for compute, S3 for objects, RDS for relational data. Define infrastructure with Terraform or CDK rather than the console, set billing alarms on day one, and prefer managed services until scale argues otherwise.