AWS Fundamentals


Cloud computing is changing the way businesses and developers build, scale, and maintain applications. One of the biggest players in this field is Amazon Web Services (AWS), the world's most comprehensive and widely adopted cloud platform. In this guide, we’ll walk you through the fundamentals of AWS, its core services, pricing models, security practices, and how to get started using AWS.


What is AWS?

Amazon Web Services (AWS) is a suite of cloud computing services offered by Amazon that enables businesses to use computing power, storage, and networking capabilities without having to manage physical infrastructure. It is the backbone for many startups, enterprises, and government agencies, providing cloud-based solutions to serve a wide variety of use cases, from hosting websites to running complex machine learning models.

AWS offers more than 200 fully-featured services in categories such as compute, storage, databases, machine learning, security, and analytics. These services are designed to be scalable, flexible, and secure, making them an ideal choice for organizations of all sizes.


Core AWS Services You Should Know

Here are the key services offered by AWS that form the backbone of cloud computing:

1. Amazon EC2 (Elastic Compute Cloud)

Amazon EC2 allows you to rent virtual servers (instances) to run your applications. You can choose from different instance types based on your application needs—whether it's compute-heavy or memory-intensive workloads. With EC2, you can scale the capacity up or down based on demand, providing flexibility for both small and large applications.

  • Use Case: Running applications, hosting websites, scaling workloads.
  • Key Features: Auto-scaling, flexible instance types, integrated security features.

2. Amazon S3 (Simple Storage Service)

Amazon S3 is an object storage service that provides highly durable and scalable storage for data, backups, and content delivery. It allows you to store virtually unlimited amounts of data, and the data is automatically replicated across multiple regions to ensure reliability and availability.

  • Use Case: Data storage, backup, disaster recovery, media hosting, and content delivery.
  • Key Features: Versioning, encryption, lifecycle management.

3. Amazon RDS (Relational Database Service)

Amazon RDS simplifies the process of setting up, operating, and scaling a relational database in the cloud. It supports various database engines like MySQL, PostgreSQL, MariaDB, Oracle, and Microsoft SQL Server. With RDS, AWS handles routine database tasks like backups, patching, and scaling, allowing you to focus on building applications.

  • Use Case: Hosting relational databases for web apps, mobile apps, and enterprise applications.
  • Key Features: Automated backups, encryption, performance monitoring.

4. Amazon Lambda

AWS Lambda is a serverless computing service that allows you to run code without provisioning or managing servers. Lambda automatically scales your code based on demand, and you only pay for the computing time your code uses. This makes it ideal for applications with variable workloads, such as event-driven architectures.

  • Use Case: Running backend services, real-time data processing, microservices.
  • Key Features: Event-driven execution, automatic scaling, pay-as-you-go pricing.

5. Amazon VPC (Virtual Private Cloud)

Amazon VPC lets you create a private network within AWS, where you can launch AWS resources in a logically isolated section of the AWS cloud. It provides full control over your network configuration, including IP address ranges, subnets, route tables, and security settings.

  • Use Case: Creating secure environments, managing network isolation, controlling traffic flow.
  • Key Features: Custom routing, private IP addressing, VPN support.

AWS Global Infrastructure

AWS operates on a global scale, with infrastructure deployed in multiple regions around the world. Each region contains multiple Availability Zones (AZs), which are isolated data centers designed to ensure high availability and fault tolerance. This global infrastructure helps ensure that your applications and services are highly available, scalable, and resilient to outages.

  • Regions: Geographically distributed locations, such as North Virginia (US East), Frankfurt (Europe), or Sydney (Asia Pacific).
  • Availability Zones: Isolated data centers within a region that allow you to distribute your applications for high availability.

The global network helps reduce latency and ensures that you can serve your users with minimal delay, no matter where they are located.


AWS Pricing Models

AWS offers flexible pricing options that allow you to pay only for the resources you use. This "pay-as-you-go" model helps reduce upfront costs and allows businesses to scale as needed without worrying about large, fixed expenses. Here are the key pricing models available in AWS:

1. On-Demand Pricing

On-demand pricing allows you to pay for compute and storage resources by the hour or second, with no upfront commitments. This model is ideal for unpredictable workloads and applications with varying usage patterns.

2. Reserved Instances

Reserved Instances allow you to reserve compute capacity in exchange for a discounted rate over a 1- or 3-year term. This is a great option for businesses with predictable workloads that need consistent capacity.

3. Spot Instances

Spot Instances enable you to bid for unused EC2 capacity at discounted rates, which can save you up to 90% compared to on-demand pricing. However, spot instances can be terminated by AWS with little notice, so they're best suited for flexible, fault-tolerant applications.

4. Free Tier

AWS offers a Free Tier for new customers to get hands-on experience with many AWS services at no charge. The Free Tier includes access to resources such as Amazon EC2, Amazon S3, and AWS Lambda with limitations (e.g., 750 hours of EC2 compute power per month for the first 12 months).


Security Best Practices in AWS

AWS provides a comprehensive set of security features to help you protect your data and applications. Below are some best practices to ensure your AWS resources are secure:

1. Use IAM (Identity and Access Management)

IAM allows you to securely control access to AWS services and resources. By creating IAM users, roles, and policies, you can manage permissions for specific users, groups, and applications. Always follow the principle of least privilege to minimize access.

2. Enable Multi-Factor Authentication (MFA)

MFA adds an additional layer of security by requiring a second form of authentication, such as a code generated by a hardware device or smartphone app, in addition to your username and password.

3. Encrypt Your Data

AWS offers encryption options for both data at rest and in transit. You can use AWS KMS (Key Management Service) to manage your encryption keys, and enable encryption on services like Amazon S3, Amazon EBS, and Amazon RDS to protect sensitive data.

4. Use AWS Shield and AWS WAF

AWS Shield provides protection against DDoS attacks, while AWS WAF (Web Application Firewall) allows you to define rules to protect your applications from common web exploits. Implementing these services helps safeguard your web applications.


How to Get Started with AWS

To start using AWS, follow these steps:

  1. Create an AWS Account: Head over to the AWS website and create your account.
  2. Explore the AWS Management Console: The AWS Console provides a web interface for managing services, creating resources, and monitoring your AWS environment.
  3. Start with AWS Free Tier: Experiment with free services like EC2, S3, and Lambda within the Free Tier to understand how AWS works.
  4. Use AWS Documentation and Tutorials: AWS offers comprehensive documentation, tutorials, and whitepapers to help you learn.
  5. Get AWS Certified: AWS offers certifications to validate your skills and knowledge, helping you advance your cloud computing career.