Cloud Computing Fundamentals
Core cloud concepts every AWS customer should understand before diving into specific services.
Cloud Computing
The on-demand delivery of IT resources (such as compute power, storage, and databases) over the internet with pay-as-you-go pricing. Instead of buying and maintaining physical data centers and servers, you access technology services from a cloud provider like AWS.
Infrastructure as a Service (IaaS)
A cloud service model that provides virtualized computing resources over the internet. With IaaS, you manage the operating system, applications, and data, while the provider manages the hardware. Example: Amazon EC2.
Platform as a Service (PaaS)
A cloud service model where the provider manages the underlying infrastructure, and you focus on deploying and managing your applications. You do not worry about hardware, operating systems, or runtime environments. Example: AWS Elastic Beanstalk.
Software as a Service (SaaS)
A cloud service model where a complete application is delivered over the internet on a subscription basis. The provider manages everything from infrastructure to the application itself. Example: Amazon WorkSpaces (virtual desktops).
Regions & Availability Zones
AWS operates in multiple geographic Regions around the world (e.g., US East, EU West). Each Region contains multiple Availability Zones (AZs) — physically separate data centers with independent power, cooling, and networking. Deploying across multiple AZs provides high availability and fault tolerance.
Edge Locations
Points of presence around the world used by services like Amazon CloudFront to cache content closer to end users, reducing latency and improving performance for global applications.
The AWS Global Infrastructure
The collective network of AWS Regions, Availability Zones, and Edge Locations worldwide. AWS spans 30+ Regions with 100+ Availability Zones and 400+ Edge Locations, enabling customers to deploy applications close to their users.
Pay-As-You-Go Pricing
The AWS billing model where you only pay for the services and resources you actually consume, with no upfront commitments or long-term contracts required. This eliminates large capital expenses and allows you to scale costs with your actual usage.
Elasticity & Scalability
Elasticity is the ability to automatically increase or decrease resources based on demand (scaling out/in). Scalability is the broader ability of a system to handle growth. AWS enables both — you can scale from one server to thousands in minutes.
High Availability & Fault Tolerance
High Availability means a system is operational and accessible most of the time (e.g., 99.99% uptime). Fault Tolerance means a system can continue operating even if individual components fail. AWS achieves this through multiple AZs, redundant systems, and automatic failover.
AWS Account & Access Management
Understanding how to manage access, identities, and permissions is critical for securing your AWS environment from day one.
AWS Account
A container for your AWS resources and the entity that is billed for usage. Each account has a unique 12-digit account ID, a root user, and its own set of IAM users, roles, and permissions.
Root User
The identity created when you first set up an AWS account. It has complete, unrestricted access to all resources. Best practice: Secure the root user with MFA, do not use it for everyday tasks, and create IAM users for daily operations.
IAM (Identity and Access Management) Service
A free AWS service that lets you securely manage access to AWS services and resources. With IAM, you create and manage users, groups, and roles, and define permissions that specify which actions are allowed or denied.
IAM Users, Groups & Roles
Users are individual identities with credentials. Groups are collections of users that share the same permissions. Roles are identities with specific permissions that can be assumed by users, applications, or AWS services — useful for granting temporary access without sharing credentials.
Policies & Permissions
JSON documents that define what actions are allowed or denied on which AWS resources. Policies are attached to users, groups, or roles. AWS uses the principle of least privilege — granting only the minimum permissions needed to perform a task.
Multi-Factor Authentication (MFA)
An additional layer of security that requires a second form of verification (such as a code from a mobile app or hardware token) in addition to a password. Strongly recommended for all IAM users, especially the root user.
AWS Organizations Service
A service that lets you centrally manage and govern multiple AWS accounts. You can group accounts into Organizational Units (OUs), apply policies across the organization, and consolidate billing for simplified cost management.
Service Control Policies (SCPs)
Policies used within AWS Organizations to set permission guardrails across accounts or OUs. SCPs define the maximum permissions available — they do not grant access but restrict what IAM policies within those accounts can allow.
AWS IAM Identity Center (formerly AWS SSO) Service
A service that makes it easy to centrally manage single sign-on access to multiple AWS accounts and business applications. Users sign in once and get access to all their assigned accounts and apps.
Compute Services
Compute services are the backbone of AWS, providing the processing power needed to run applications, websites, and workloads of all sizes.
Amazon EC2 (Elastic Compute Cloud) Service
A web service that provides resizable virtual servers (called instances) in the cloud. EC2 gives you complete control over your computing resources and lets you run applications on Amazon's computing infrastructure. You choose the operating system, instance size, and configuration.
Instance Types
EC2 instances come in various types optimized for different workloads. Families include General Purpose (t3, m5), Compute Optimized (c5), Memory Optimized (r5), Storage Optimized (i3), and Accelerated Computing (p4, g5) for GPU workloads. Each type offers a different balance of CPU, memory, storage, and networking.
AMI (Amazon Machine Image)
A pre-configured template that contains the operating system, application server, and applications needed to launch an EC2 instance. AMIs let you quickly launch multiple instances with identical configurations. You can use AWS-provided AMIs, community AMIs, or create your own.
AWS Lambda Service
A serverless compute service that lets you run code without provisioning or managing servers. You upload your code, and Lambda automatically scales and runs it in response to events (such as HTTP requests, file uploads, or database changes). You pay only for the compute time you consume.
Amazon ECS & EKS (Containers) Service
Amazon ECS (Elastic Container Service) is a fully managed container orchestration service for running Docker containers. Amazon EKS (Elastic Kubernetes Service) provides managed Kubernetes clusters. Both let you run containerized applications at scale without managing the underlying infrastructure.
AWS Fargate Service
A serverless compute engine for containers that works with both ECS and EKS. With Fargate, you do not need to provision or manage servers — you specify the CPU and memory requirements, and AWS handles the infrastructure.
AWS Elastic Beanstalk Service
A Platform-as-a-Service (PaaS) that makes it easy to deploy and manage web applications. You upload your code, and Elastic Beanstalk automatically handles deployment, capacity provisioning, load balancing, auto scaling, and health monitoring.
Auto Scaling
A feature that automatically adjusts the number of EC2 instances (or other resources) based on demand. When traffic increases, Auto Scaling adds instances; when traffic decreases, it removes them. This ensures you have the right amount of resources at all times while minimizing costs.
Elastic Load Balancing (ELB) Service
A service that automatically distributes incoming application traffic across multiple targets (such as EC2 instances, containers, or IP addresses). ELB improves application availability and fault tolerance. Types include Application Load Balancer (HTTP/HTTPS), Network Load Balancer (TCP/UDP), and Gateway Load Balancer.
Storage Services
AWS offers a range of storage services designed for different use cases — from object storage for files and media to block storage for databases and file systems.
Amazon S3 (Simple Storage Service) Service
An object storage service offering virtually unlimited scalability, data availability, security, and performance. S3 stores data as objects within buckets and is commonly used for backup, archiving, content distribution, data lakes, and static website hosting. Objects can range from 0 bytes to 5 TB.
S3 Storage Classes
S3 offers multiple storage classes for different access patterns and cost requirements: S3 Standard (frequent access), S3 Intelligent-Tiering (automatic cost optimization), S3 Standard-IA (infrequent access), S3 One Zone-IA, S3 Glacier Instant Retrieval, S3 Glacier Flexible Retrieval, and S3 Glacier Deep Archive (long-term archive).
Amazon EBS (Elastic Block Store) Service
Provides persistent block-level storage volumes for EC2 instances. Think of EBS as a virtual hard drive that persists independently from the life of an instance. Ideal for databases, file systems, and applications requiring frequent reads and writes.
Amazon EFS (Elastic File System) Service
A fully managed, elastic file system that can be shared across multiple EC2 instances simultaneously. EFS automatically grows and shrinks as you add and remove files, and is ideal for shared storage, content management, and big data workloads.
Amazon S3 Glacier Service
A set of S3 storage classes designed for data archiving and long-term backup at very low cost. Retrieval times range from milliseconds (Glacier Instant Retrieval) to hours (Glacier Deep Archive). Ideal for compliance data, medical records, and other data that is rarely accessed.
AWS Storage Gateway Service
A hybrid cloud storage service that provides on-premises access to virtually unlimited cloud storage. It connects your on-premises environment to AWS storage services, making it useful for backup, disaster recovery, and tiered storage while integrating with existing applications.
AWS Backup Service
A fully managed service that centralizes and automates data backup across AWS services (EC2, EBS, RDS, DynamoDB, EFS, and more). It provides a single place to configure backup policies, monitor activity, and restore resources.
Networking & Content Delivery
Networking services let you define and control how your resources communicate with each other and the outside world, while content delivery services ensure fast, global access.
Amazon VPC (Virtual Private Cloud) Service
A logically isolated section of the AWS cloud where you can launch resources in a virtual network that you define. You have complete control over your networking environment — including IP address ranges, subnets, route tables, and gateways. Think of it as your own private data center in the cloud.
Subnets (Public & Private)
Subdivisions of a VPC's IP address range where you place resources. Public subnets have a route to the internet via an Internet Gateway (for web servers, load balancers). Private subnets have no direct internet access (for databases, application servers) and are accessed only through a NAT Gateway or VPN.
Internet Gateway & NAT Gateway
An Internet Gateway (IGW) allows resources in public subnets to communicate with the internet. A NAT Gateway allows resources in private subnets to access the internet for updates and patches while preventing inbound connections from the internet.
Security Groups & Network ACLs
Security Groups act as virtual firewalls for individual resources (e.g., EC2 instances), controlling inbound and outbound traffic at the instance level. They are stateful (return traffic is automatically allowed). Network ACLs operate at the subnet level, are stateless, and provide an additional layer of defense.
Amazon Route 53 Service
A highly available and scalable Domain Name System (DNS) web service. Route 53 translates domain names (like www.example.com) into IP addresses, routes users to your application, and provides health checking and DNS failover capabilities.
Amazon CloudFront Service
A fast content delivery network (CDN) service that securely delivers data, videos, applications, and APIs to users globally with low latency. CloudFront caches content at Edge Locations around the world, so users receive content from the location nearest to them.
AWS Direct Connect Service
A dedicated private network connection between your on-premises data center and AWS. Direct Connect bypasses the public internet, providing more consistent network performance, lower latency, and higher bandwidth — ideal for hybrid cloud architectures and large data transfers.
Elastic IP Addresses
Static, public IPv4 addresses that you can allocate to your AWS account and associate with EC2 instances or other resources. Unlike regular public IPs that change when an instance is stopped, Elastic IPs remain fixed, making them useful for DNS and failover scenarios.
VPC Peering & Transit Gateway
VPC Peering creates a private connection between two VPCs, allowing them to communicate as if they were on the same network. AWS Transit Gateway acts as a central hub connecting multiple VPCs and on-premises networks, simplifying network architecture at scale.
Database Services
AWS offers purpose-built database services for every application need — from relational and NoSQL databases to data warehousing and in-memory caching.
Amazon RDS (Relational Database Service) Service
A managed service that makes it easy to set up, operate, and scale relational databases in the cloud. RDS handles routine tasks like provisioning, patching, backups, and replication. Supports engines including MySQL, PostgreSQL, MariaDB, Oracle, SQL Server, and Amazon Aurora.
Amazon Aurora Service
A MySQL- and PostgreSQL-compatible relational database engine built for the cloud. Aurora is up to 5x faster than standard MySQL and 3x faster than standard PostgreSQL, with the availability and durability of commercial databases at a fraction of the cost.
Amazon DynamoDB Service
A fully managed NoSQL (non-relational) database service that delivers single-digit millisecond performance at any scale. DynamoDB is ideal for applications that need consistent, low-latency data access — such as gaming, IoT, mobile apps, and e-commerce.
Amazon Redshift Service
A fast, fully managed cloud data warehouse that lets you analyze large volumes of data using standard SQL and existing business intelligence tools. Redshift can handle petabytes of structured and semi-structured data for analytics and reporting.
Amazon ElastiCache Service
A fully managed in-memory caching service supporting Redis and Memcached. ElastiCache improves application performance by retrieving data from fast in-memory caches instead of slower disk-based databases. Common uses include session stores, leaderboards, and real-time analytics.
Amazon DocumentDB Service
A fully managed document database service compatible with MongoDB workloads. DocumentDB is designed for storing, querying, and indexing JSON data, making it ideal for content management, catalogs, and user profiles.
Security & Compliance
Security is the top priority at AWS. These services and concepts help you protect your data, manage encryption, detect threats, and maintain compliance.
AWS Shared Responsibility Model
The framework that defines the division of security responsibilities between AWS and the customer. AWS is responsible for security OF the cloud (physical infrastructure, hardware, networking). The customer is responsible for security IN the cloud (data, IAM, application configuration, encryption, OS patching).
AWS Shield Service
A managed Distributed Denial of Service (DDoS) protection service. Shield Standard is automatically included at no extra cost and protects against common attacks. Shield Advanced provides enhanced protections, 24/7 access to the DDoS Response Team, and cost protection for scaling during attacks.
AWS WAF (Web Application Firewall) Service
A web application firewall that helps protect your applications from common web exploits like SQL injection, cross-site scripting (XSS), and bot traffic. WAF lets you create custom rules to allow, block, or monitor web requests based on conditions you define.
Amazon GuardDuty Service
An intelligent threat detection service that continuously monitors your AWS accounts, workloads, and data for malicious activity and unauthorized behavior. GuardDuty uses machine learning, anomaly detection, and integrated threat intelligence to identify potential threats.
AWS Key Management Service (KMS) Service
A managed service for creating and controlling encryption keys used to encrypt your data across AWS services. KMS integrates with most AWS services, making it easy to encrypt data stored in S3, EBS, RDS, and more.
AWS CloudTrail Service
A service that records API calls and account activity across your AWS infrastructure. CloudTrail logs provide a complete audit trail of who did what, when, and from where — essential for security analysis, compliance auditing, and troubleshooting.
AWS Config Service
A service that continuously monitors and records your AWS resource configurations and evaluates them against desired settings. Config helps you assess compliance, track changes over time, and understand relationships between resources.
Amazon Inspector Service
An automated security assessment service that scans your EC2 instances, container images, and Lambda functions for software vulnerabilities and unintended network exposure. Inspector provides detailed findings with prioritized remediation guidance.
AWS Secrets Manager Service
A service that helps you manage, retrieve, and rotate credentials (such as database passwords, API keys, and tokens) throughout their lifecycle. Secrets Manager eliminates the need to hardcode sensitive information in your applications.
Management & Monitoring
Tools for managing your AWS environment, monitoring performance, automating infrastructure, and controlling costs.
AWS Management Console
A web-based graphical interface for accessing and managing AWS services. The console provides a visual way to create and configure resources, view dashboards, and manage your account. It is the most beginner-friendly way to interact with AWS.
AWS CLI (Command Line Interface)
A unified tool for managing AWS services from the command line. The CLI lets you control multiple AWS services, automate tasks through scripts, and is often faster than the console for experienced users.
Amazon CloudWatch Service
A monitoring and observability service that collects metrics, logs, and events from your AWS resources and applications. CloudWatch provides dashboards, alarms, and automated actions — enabling you to monitor performance, troubleshoot issues, and optimize resource utilization.
AWS CloudFormation Service
An Infrastructure as Code (IaC) service that lets you define your entire cloud infrastructure in template files (JSON or YAML). CloudFormation provisions and manages resources automatically based on your templates, ensuring consistent, repeatable deployments.
AWS Systems Manager Service
A collection of tools for managing your AWS resources at scale. Systems Manager provides patch management, configuration management, remote access (Session Manager), parameter storage, and automation capabilities for your EC2 instances and on-premises servers.
AWS Trusted Advisor Service
An online tool that inspects your AWS environment and provides real-time recommendations to help you optimize costs, improve performance, enhance security, and increase fault tolerance based on AWS best practices.
AWS Cost Explorer Service
A tool that lets you visualize, understand, and manage your AWS costs and usage over time. Cost Explorer provides interactive charts, filters, and forecasts to help you analyze spending patterns and identify savings opportunities.
AWS Budgets Service
A service that lets you set custom cost and usage budgets and receive alerts when your actual or forecasted spending exceeds your thresholds. Budgets can trigger notifications or automated actions to help prevent unexpected charges.
Additional Key Services
Beyond the core categories, these frequently used services support messaging, analytics, machine learning, and developer workflows.
Amazon SNS (Simple Notification Service) Service
A fully managed messaging service for sending notifications. SNS supports publishing messages to multiple subscribers via email, SMS, HTTP endpoints, or other AWS services. Commonly used for alerts, notifications, and decoupling microservices.
Amazon SQS (Simple Queue Service) Service
A fully managed message queuing service that enables you to decouple and scale microservices, distributed systems, and serverless applications. SQS stores messages in a queue until they are processed, ensuring reliable communication between components.
Amazon SES (Simple Email Service) Service
A cost-effective, scalable email service for sending transactional emails, marketing messages, and other types of content to customers. SES handles email deliverability, bounce management, and complaint tracking.
AWS Step Functions Service
A serverless orchestration service that lets you coordinate multiple AWS services into serverless workflows (called state machines). Step Functions make it easy to build and visualize complex, multi-step processes with error handling and retry logic.
Amazon Kinesis Service
A platform for collecting, processing, and analyzing real-time streaming data at any scale. Kinesis enables you to ingest data from sources like IoT devices, application logs, clickstreams, and social media for real-time dashboards, analytics, and machine learning.
Amazon SageMaker Service
A fully managed machine learning service that enables data scientists and developers to build, train, and deploy machine learning models quickly. SageMaker provides built-in algorithms, Jupyter notebooks, and one-click deployment for ML models.
AWS Glue Service
A fully managed extract, transform, and load (ETL) service that makes it easy to prepare and load data for analytics. Glue automatically discovers data, generates ETL code, and loads data into data stores like S3 or Redshift.
Amazon Athena Service
An interactive query service that lets you analyze data directly in Amazon S3 using standard SQL. Athena is serverless — there is no infrastructure to manage, and you pay only for the queries you run. Ideal for ad-hoc analysis of log files, clickstream data, and more.
AWS CodePipeline / CodeBuild / CodeDeploy Service
A suite of developer tools for continuous integration and continuous delivery (CI/CD). CodePipeline automates the build, test, and deploy phases. CodeBuild compiles source code and runs tests. CodeDeploy automates deployments to EC2 instances, Lambda functions, or on-premises servers.
AWS Support & Resources
AWS provides extensive resources to help you learn, build, and get assistance as you grow on the platform.
AWS Support Plans
AWS offers multiple support tiers: Basic (free, documentation and community forums), Developer (business-hours email support), Business (24/7 phone, email, and chat support with faster response times), and Enterprise (dedicated Technical Account Manager, proactive guidance, and 15-minute response for critical issues).
AWS Well-Architected Framework
A set of best practices and guidelines organized into six pillars: Operational Excellence, Security, Reliability, Performance Efficiency, Cost Optimization, and Sustainability. The framework helps you evaluate and improve your cloud architectures against industry best practices.
AWS Training & Certification
Free and paid learning resources including digital courses, classroom training, and certification exams. AWS certifications (Cloud Practitioner, Solutions Architect, Developer, SysOps, and specialty certifications) validate your cloud expertise and are recognized across the industry.
AWS Free Tier
A program that lets new customers explore and try AWS services free of charge within certain usage limits. The Free Tier includes Always Free offers (services with limits that never expire), 12-Month Free offers (free for the first year), and short-term trials of specific services.
AWS Marketplace
A digital catalog with thousands of software listings from independent software vendors. You can find, test, buy, and deploy software that runs on AWS — including AMIs, SaaS applications, machine learning models, and data products — with flexible pricing and one-click deployment.