AWS Cheatsheet: A Beginner-Friendly Guide

Introduction

Amazon Web Services (AWS) is one of the most popular cloud platforms that provides different services for computing, storage, databases, networking, and more. Learning AWS can feel overwhelming because there are many services available, but a cheatsheet can help you quickly recall the important ones. This article explains the most useful AWS services in simple terms, with short examples and important notes.

1. EC2 (Elastic Compute Cloud)

Definition: A virtual server that runs applications in the cloud.

Example:

aws ec2 run-instances --image-id ami-123456 --count 1 --instance-type t2.micro

Point: Choose the instance type based on CPU, memory, and workload needs.

2. S3 (Simple Storage Service)

Definition: A storage service for storing any type of file (object storage).
Example:
```
aws s3 cp file.txt s3://mybucket/
```
Point: Data is stored in buckets. You can set permissions and make files public or private.

3. RDS (Relational Database Service)

Definition: Managed databases like MySQL, PostgreSQL, or SQL Server.

Example:

aws rds create-db-instance --db-instance-identifier mydb --engine mysql

Point: AWS manages backups, updates, and scaling for you.

4. Lambda

Definition: A service to run code without managing servers.

Example:

def handler(event, context):
    return "Hello from Lambda"

Point: Pay only for the time your code runs.

5. IAM (Identity and Access Management)

Definition: Controls who can access AWS services and resources.
Example: Create a new IAM user with limited permissions.
```
aws iam create-user --user-name newuser
```
Point: Always follow the principle of least privilege.

6. VPC (Virtual Private Cloud)

Definition: A private network inside AWS for your resources.
Point: You can set subnets, route tables, and security groups to control traffic.

7. CloudFront

Definition: A content delivery network (CDN) that delivers files faster by caching them worldwide.
Point: Often used with S3 for hosting websites.

8. DynamoDB

Definition: A fully managed NoSQL database.

Example

aws dynamodb create-table --table-name Users --attribute-definitions ...

Point: Best for applications that need fast and scalable performance.

9. SNS (Simple Notification Service)

Definition: Sends notifications through email, SMS, or push messages.

Example

aws sns publish --topic-arn arn:aws:sns:us-east-1:123456:mytopic --message "Hello"

Point: Good for sending alerts or updates automatically.

10. SQS (Simple Queue Service)

Definition: A message queue to store and process messages between systems.

Example

aws sqs send-message --queue-url <url> --message-body "Task1"

Point: Helps decouple applications so they can work independently.

11. CloudWatch

Definition: A Monitoring service for AWS resources and applications.
Point: You can track metrics, set alarms, and view logs.

12. Elastic Beanstalk

Definition: Deploy and manage applications without worrying about servers.
Point: You just upload your code, and Beanstalk handles scaling and deployment.

13. EBS (Elastic Block Store)

Definition: Persistent storage volumes for EC2 instances.
Point: Similar to a hard drive that you can attach to your instance.

14. Route 53

Definition: A scalable domain name system (DNS) service.
Point: It connects domain names to AWS resources or other servers.

15. CloudFormation

Definition: Infrastructure as code service to create and manage AWS resources using templates.
Point: Useful for automating resource deployment.

16. ECS (Elastic Container Service) and EKS (Elastic Kubernetes Service)

Definition: Container orchestration services for running Docker or Kubernetes workloads.
Point: ECS is AWS-managed, while EKS lets you run Kubernetes clusters.

17. AWS CLI

Definition: A command-line tool to interact with AWS services.
Example
```
aws s3 ls
```
Point: Faster than clicking in the AWS console for repetitive tasks.

Conclusion

AWS has many services, but focusing on the most commonly used ones makes it easier to understand and work with cloud computing. EC2, S3, RDS, Lambda, IAM, and VPC are the core services, while others like DynamoDB, CloudWatch, and SNS add more capabilities. Keep this cheatsheet handy as a quick reference while learning or working on AWS.