AWS EC2 — Complete Beginner Guide (Instances, Pricing, Use Cases)

AWS EC2 — Complete Beginner Guide (Instances, Pricing, Use Cases)

What Is EC2?

Amazon EC2 (Elastic Compute Cloud) provides virtual servers known as instances. It allows you to run applications without managing physical hardware.

Types of EC2 Instances

• General Purpose: t3, t4g
• Compute Optimized: c6i
• Memory Optimized: r6g
• GPU Instances: p4, g5
• Storage Optimized: i4

EC2 Pricing Models

On-Demand

Pay per second/hour. Most flexible but expensive.

Reserved Instances

Commit 1–3 years. Up to 72% cheaper.

Spot Instances

Use AWS unused capacity. Up to 90% cheaper. Best for batch jobs & ML training.

Key EC2 Features

• Security Groups
• EBS Block Storage
• Elastic Load Balancing
• Auto Scaling

When to Use EC2?

• Web applications
• Backend APIs
• Gaming servers
• Databases
• Machine learning workloads

Conclusion

EC2 is a core AWS service. Knowing its pricing and instance types is essential for cloud beginners.

AWS VPC — Beginner-Friendly Explanation with Real Examples

AWS VPC — Beginner-Friendly Explanation with Real Examples

What Is VPC?

A Virtual Private Cloud (VPC) is your own isolated network inside AWS. You control IP ranges, subnets, routing, and security.

Core Components of VPC

• Subnets: Public & private
• Route Tables
• Internet Gateway
• NAT Gateway
• Security Groups
• Network ACLs

Example VPC Architecture

• Public subnet → EC2 + Load Balancer
• Private subnet → Database
• NAT Gateway → Internet access for private subnet
• Security Groups → Allow specific ports

Why VPC Is Important?

• High security
• Custom network control
• Multi-layer architecture
• Used in enterprise cloud setups

Conclusion

VPC is the backbone of AWS networking. Every cloud learner must understand its structure and components.

AWS Cloud Practitioner — 20 Most Expected Questions (With Answers)

AWS Cloud Practitioner — 20 Most Expected Questions (With Answers)

1. What is Cloud Computing? Internet-based computing.
2. What is EC2? Virtual server.
3. What is S3 durability? 99.999999999%.
4. What is an Availability Zone? Physical data center.
5. What is the root account? Primary admin account.
6. What is IAM? Identity management system.
7. What is VPC? Virtual private network.
8. What is Lambda? Serverless compute.
9. What is RDS? Managed database service.
10. What is CloudFront? Content delivery network.
11. What is Multi-AZ? Failover for RDS.
12. What is Route 53? DNS service.
13. What is Auto Scaling? Adds/removes EC2s automatically.
14. What is ELB? Distributes traffic.
15. What is Elastic Beanstalk? Simple app deployment.
16. What is KMS? Key management service.
17. What is SNS? Notification service.
18. What is SQS? Message queue.
19. What is Glacier? Long-term storage.
20. What is CloudTrail? Audit logs.

These questions help you prepare for AWS Cloud Practitioner exam with confidence.

What Is Cloud Computing? A Simple Guide for Beginners (2025 Update)

Introduction

Cloud computing allows you to access computing services such as servers, storage, databases, and software over the internet. Instead of maintaining physical infrastructure, you use cloud providers like AWS, Azure, and Google Cloud.

Why Cloud Computing Is Popular

• No need to buy expensive servers
• Pay only for what you use
• Faster application development
• High-level security
• Global reach and scalability

Types of Cloud Services

IaaS – Infrastructure as a Service

Provides servers, storage, and networking. Examples: AWS EC2, Azure VM.

PaaS – Platform as a Service

Provides application platforms. Examples: AWS Elastic Beanstalk, Heroku.

SaaS – Software as a Service

Provides ready-made applications. Examples: Gmail, Netflix, Google Docs.

Cloud Deployment Models

• Public Cloud: Used by everyone (AWS, Azure)
• Private Cloud: Used internally by organizations
• Hybrid Cloud: Mix of public + private

Real-Life Examples

• YouTube stores videos in cloud storage
• Instagram photos are stored like S3 objects
• Online banking uses secure cloud networks

Benefits of Cloud Computing

• Cost-efficient
• Highly available
• Automatic scaling
• Strong security
• Reliable backup and recovery

Conclusion

Cloud computing is the backbone of modern technology. Understanding its basics is important for students, developers, and IT professionals.

AWS S3 Explained: Buckets, Storage Classes, Security & Use Cases

AWS S3 Explained — Buckets, Storage Classes, Security & Use Cases

What Is Amazon S3?

Amazon S3 (Simple Storage Service) is an object storage service that provides 11 nines durability (99.999999999%). It stores data as objects inside buckets.

Core S3 Concepts

• Buckets: Top-level container
• Objects: Files stored inside buckets
• Keys: Object names
• Versioning: Tracks old versions of objects
• Encryption: SSE-S3, SSE-KMS

Storage Classes

• S3 Standard
• S3 Infrequent Access (IA)
• S3 One Zone IA
• S3 Glacier
• S3 Glacier Deep Archive

Useful S3 Features

• Bucket policies
• Lifecycle rules
• Cross-Region Replication
• S3 Events (trigger Lambda)
• Access Control Lists

Use Cases

• Static website hosting
• Backups and archives
• Data lakes
• Log storage
• Machine learning datasets

Conclusion

S3 is the most flexible cloud storage solution. It is widely used in multiple industries and AWS exams.

IAM Roles, Policies & Users Explained — With Easy Memory Tricks

AWS IAM — Roles, Users, Groups & Policies Explained

What Is IAM?

AWS Identity & Access Management (IAM) is used to control who can access which AWS resources.

IAM Components

• Users: Individual login accounts
• Groups: Collection of users
• Roles: Temporary permissions for AWS services
• Policies: JSON-based permission documents

Easy Memory Trick

• User = Person
• Group = Team
• Role = Temporary identity
• Policy = Rule book

Security Best Practices

• Enable MFA
• Don’t use root account
• Use least privilege access
• Rotate access keys

Conclusion

IAM ensures secure access to AWS resources and is one of the most important cloud concepts.

AWS Lambda Simplified — What It Is, How It Works & When To Use It

AWS Lambda Simplified — What It Is, How It Works & When To Use It

What Is Serverless?

Serverless computing means you don’t manage servers, capacity, or scaling. The cloud provider (AWS) takes care of all the infrastructure behind the scenes so you can focus only on code.

What Is AWS Lambda?

AWS Lambda is a serverless compute service that lets you run code without provisioning servers. It supports multiple languages such as Python, Node.js, Java, Go, and more.

How AWS Lambda Works

1. Create a Lambda function
2. Add your application code
3. Set a trigger (S3, DynamoDB, API Gateway, EventBridge, CloudWatch, etc.)
4. AWS automatically runs and scales your function

Lambda Pricing

You pay only for:

• Total number of requests
• Execution time (measured in milliseconds)

There are no charges when the function is idle, which makes Lambda extremely cost-effective.

Common Use Cases of AWS Lambda

• Real-time file processing
• API backend (with API Gateway)
• Cron jobs & scheduled tasks
• IoT event processing
• Machine learning lightweight inference

Lambda vs EC2 (Simple Comparison)

Feature	AWS Lambda	Amazon EC2
Server Management	No servers (fully managed)	You manage everything
Scaling	Auto, instant	Manual or auto
Pricing	Pay only per request & execution	Pay per hour/second even if idle
Best For	Event-driven apps, microservices	Long-running apps

Conclusion

AWS Lambda is perfect for automation, microservices, event-driven workloads, and modern cloud-native applications. It is a crucial topic for AWS Cloud Practitioner and Associate-level cloud learners.