# Cloud Glossary > A comprehensive free glossary of cloud computing terms, definitions, and concepts covering AWS, Azure, Google Cloud, and fundamental cloud technologies from A to Z. Cloud Glossary provides clear, concise definitions for cloud computing terminology used by developers, IT professionals, and businesses. The glossary covers major cloud service models (IaaS, PaaS, SaaS), cloud deployment models (public, private, hybrid), key technologies (virtualization, containerization), and platform-specific services from major providers. The site is organized alphabetically with terms ranging from basic concepts like "Cloud Computing" and "Scalability" to specific services like "Amazon EC2" and "Google Apps" (now Google Workspace). Each term includes a detailed explanation suitable for both beginners and experienced professionals. ## Core Cloud Concepts - [Infrastructure as a Service (IaaS)](https://cloudglossary.com/infrastructure-as-a-service-iaas): Fundamental cloud service model providing virtualized computing resources - [Platform as a Service (PaaS)](https://cloudglossary.com/platform-as-a-service-paas): Cloud computing model providing development platforms for applications - [Software as a Service (SaaS)](https://cloudglossary.com/software-as-a-service-saas): Cloud computing model delivering software applications over the internet - [Public Cloud](https://cloudglossary.com/public-cloud): Cloud computing model where services are provided over the public internet - [Private Cloud](https://cloudglossary.com/private-cloud): Cloud computing environment dedicated to a single organization - [Hybrid Cloud](https://cloudglossary.com/hybrid-cloud): Cloud computing environment combining public and private cloud elements ## Major Cloud Platforms - [Amazon Web Services (AWS)](https://cloudglossary.com/amazon-web-services-aws): Comprehensive cloud computing platform from Amazon - [Azure](https://cloudglossary.com/azure): Microsoft's comprehensive cloud services platform - [Amazon EC2](https://cloudglossary.com/amazon-ec2): Amazon's Elastic Compute Cloud service for scalable computing - [Amazon S3](https://cloudglossary.com/amazon-s3): Amazon Simple Storage Service for scalable cloud storage - [Google Apps](https://cloudglossary.com/google-apps): Google's suite of cloud-based productivity applications (now Google Workspace) ## Key Technologies & Frameworks - [Apache Hadoop](https://cloudglossary.com/apache-hadoop): Open-source framework for distributed storage and processing - [Virtual Machine (VM)](https://cloudglossary.com/virtual-machine-vm): Software-based emulation of physical computer systems - [Multitenancy](https://cloudglossary.com/multitenancy): Architectural principle where single instances serve multiple tenants - [Scalability](https://cloudglossary.com/scalability): Ability of systems to handle increased workload demands - [Rapid Elasticity](https://cloudglossary.com/rapid-elasticity): Cloud characteristic enabling dynamic resource scaling ## Business & Pricing Models - [Subscription Based Pricing Model](https://cloudglossary.com/subscription-based-pricing-model): Financial strategy for recurring cloud service payments - [Utility Computing](https://cloudglossary.com/utility-computing): Service model where computing resources are provided on-demand - [Measured Service](https://cloudglossary.com/measured-service): Cloud characteristic enabling automatic resource monitoring and billing ## Optional - [NIST](https://cloudglossary.com/national-institute-of-standards-and-technology-nist): National Institute of Standards and Technology cloud definitions - [Vendor Lock In](https://cloudglossary.com/vendor-lock-in): Situation where customers become dependent on specific cloud providers - [Federation](https://cloudglossary.com/federation): Practice of interconnecting multiple cloud environments - [Content Delivery Network](https://cloudglossary.com/content-delivery-network): Distributed network of servers for content delivery optimization