AWS Glossary
Clear, accurate definitions of every AWS service and concept. From EC2 and S3 to IAM and the Well-Architected Framework — no jargon, just answers.
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AWS Well-Architected Framework: The 6 Pillars Explained
The AWS Well-Architected Framework codifies best practices across 6 pillars: Operational Excellence, Security, Reliability, Performance, Cost, and Sustainability. Learn each.
AWS Step Functions: Serverless Workflow Orchestration
AWS Step Functions orchestrates Lambda, ECS, and other AWS services into durable state machines. Learn Standard vs Express workflows, ASL, error handling, and pricing.
Amazon SQS: Message Queue Service on AWS Explained
Amazon SQS is AWS's managed message queue service. Learn Standard vs FIFO queues, visibility timeout, dead-letter queues, polling, pricing, and when to use SQS vs SNS or Kinesis.
SQS vs SNS: When to Use Each (and the Fan-Out Pattern)
Compare Amazon SQS (pull-based queue) vs Amazon SNS (push-based pub/sub). Learn the SNS→SQS fan-out pattern, when to pick each, and how EventBridge fits in.
Amazon SNS: Pub/Sub Messaging for AWS Explained
Amazon SNS is AWS's managed pub/sub service. Learn topics, subscriptions, fan-out to SQS/Lambda/email/SMS, FIFO topics, message filtering, and when to use SNS vs EventBridge.
AWS Savings Plans: Save up to 72% on EC2, Lambda & Fargate
AWS Savings Plans discount EC2, Fargate, Lambda, and SageMaker by up to 72% for a 1- or 3-year commitment. Learn Compute vs EC2 Instance vs SageMaker plans.
S3 Storage Classes: Compare Pricing, Latency & Durability
Amazon S3 offers 8 storage classes from Standard to Glacier Deep Archive. Compare pricing, retrieval time, minimum storage, durability, and when to choose each class.
Amazon CloudWatch: AWS Metrics, Logs, Alarms & Dashboards
Amazon CloudWatch is AWS's monitoring and observability service. Learn metrics, logs, alarms, events/EventBridge, Logs Insights, Container Insights, and pricing.
AWS CloudTrail: Audit Logs for Every AWS API Call
AWS CloudTrail records every API call in your account for security, auditing, and compliance. Learn Management Events, Data Events, Insights, Lake, and CloudTrail vs CloudWatch.
Availability Zone (AZ): What It Is and Why It Matters
An AWS Availability Zone is one or more discrete data centers inside a Region with redundant power, networking, and cooling. Learn how AZs enable high availability and how to design for multi-AZ.
Frequently Asked Questions
QWhat is Amazon EC2?
Amazon EC2 (Elastic Compute Cloud) is AWS's core service for renting virtual servers in the cloud. You pick an instance type (CPU, memory, network), an Amazon Machine Image (AMI) that contains the OS and software, and EC2 launches the server in minutes. You pay per second for compute capacity, with discounts available through Savings Plans, Reserved Instances, or Spot Instances.
QWhat is the difference between S3 and EBS?
Amazon S3 is object storage for files, backups, and static websites — accessed over HTTPS, not mounted as a disk. Amazon EBS (Elastic Block Store) provides block-level storage volumes that attach to EC2 instances like a hard drive. Use S3 for unstructured data and shared access; use EBS when an application needs a regular filesystem attached to a single EC2 instance.
QWhat is an IAM role vs an IAM user?
An IAM user represents a specific human or service with long-term credentials (password, access keys). An IAM role is an identity with permissions that is assumed temporarily — typically by an AWS service (like EC2 or Lambda) or by federated users. Best practice is to use roles for workloads and IAM Identity Center (SSO) for humans, instead of long-lived user credentials.
QWhich AWS certification should I start with?
Most people start with AWS Certified Cloud Practitioner (CLF-C02) for a foundational overview, then move to AWS Certified Solutions Architect Associate (SAA-C03) — the most popular associate-level certification. If you already have cloud or development experience, you can skip CLF-C02 and start with SAA-C03 or Developer Associate (DVA-C02) directly.