Cloud Computing Glossary: AWS, Azure, and GCP Terms Explained
Complete glossary of cloud computing, DevOps, and infrastructure terms for 2026. Every concept from containers to serverless.
A — API Gateway to Auto-scaling
API Gateway: A service that manages, secures, and routes API requests. API gateways handle authentication, rate limiting, request transformation, and load balancing. AWS API Gateway, Kong, and Nginx are popular options. In 2026, API gateways are critical infrastructure for microservices architectures. Availability Zone (AZ): A physically separate data center within a cloud region. Deploying across multiple AZs provides fault tolerance — if one data center fails, others continue serving. AWS has 3-6 AZs per region. Auto-scaling: Automatically adjusting compute resources based on demand. Scale up during traffic spikes, scale down during quiet periods. Auto-scaling reduces costs by 30-70% compared to fixed provisioning. Horizontal scaling adds more instances; vertical scaling adds more CPU/RAM to existing instances.
C — CDN to Containers
CDN (Content Delivery Network): A distributed network of servers that caches and serves content from locations closest to users, reducing latency and load on origin servers. Major CDNs include Cloudflare, AWS CloudFront, Fastly, and Akamai. CI/CD (Continuous Integration/Continuous Deployment): Development practices that automate building, testing, and deploying code. CI merges and tests code changes frequently. CD automatically deploys tested changes to production. Tools include GitHub Actions, GitLab CI, Jenkins, and CircleCI. Container: A lightweight, isolated environment for running applications with all their dependencies. Containers share the host OS kernel, making them faster and smaller than virtual machines. Docker is the standard container format. Kubernetes orchestrates containers at scale.
D-F — DevOps to Functions
DevOps: A culture and set of practices that combines software development (Dev) and IT operations (Ops) to shorten the development lifecycle and deliver high-quality software continuously. DevOps emphasizes automation, monitoring, collaboration, and infrastructure as code. DNS: The Domain Name System translates human-readable domain names (example.com) to IP addresses. Cloud DNS services (Route 53, Cloud DNS, Azure DNS) offer programmatic management, health checks, and geographic routing. FaaS (Functions as a Service): Running individual functions in the cloud without managing servers. Each function executes in response to an event (HTTP request, database change, message queue). AWS Lambda, Google Cloud Functions, and Azure Functions are the major providers. Functions scale automatically and you pay only for execution time.
I — IaC to Infrastructure
IaC (Infrastructure as Code): Managing and provisioning infrastructure through code files rather than manual processes. IaC enables version control, reproducibility, and automation of infrastructure. Terraform: The most popular multi-cloud IaC tool, using HCL (HashiCorp Configuration Language). Pulumi uses general-purpose languages (Python, TypeScript). AWS CloudFormation is AWS-specific. Immutable Infrastructure: A pattern where servers are never modified after deployment — instead, new servers are built from scratch with updated configurations. This eliminates configuration drift and ensures consistency. Instance: A virtual server running in the cloud. EC2 instances (AWS), Compute Engine VMs (GCP), and Azure VMs are the primary compute services. Instance types vary by CPU, RAM, GPU, and storage optimized for different workloads.
K — Kubernetes to K8s Concepts
Kubernetes (K8s): An open-source container orchestration platform that automates deploying, scaling, and managing containerized applications. Originally developed by Google, now maintained by the CNCF. Kubernetes runs on all major clouds (EKS, GKE, AKS) and on-premise. Pod: The smallest deployable unit in Kubernetes — one or more containers that share networking and storage. Service: A stable network endpoint that routes traffic to pods. Deployment: A declarative configuration that manages pod replicas and rolling updates. Namespace: A virtual cluster within Kubernetes for resource isolation. Helm: A package manager for Kubernetes that bundles configurations into reusable charts. In 2026, Kubernetes is the de facto standard for running containerized applications at scale.
L-M — Load Balancer to Microservices
Load Balancer: A device or service that distributes incoming traffic across multiple servers. Layer 4 load balancers route by IP/port. Layer 7 load balancers route by HTTP content (URL, headers, cookies). Cloud load balancers (ALB, NLB, Cloud Load Balancing) integrate with auto-scaling. Managed Service: A cloud service where the provider handles infrastructure management (patching, scaling, backups). Examples: RDS (managed databases), ElastiCache (managed Redis), Cloud SQL. Managed services reduce operational burden but cost more than self-managed alternatives. Microservices: An architecture where applications are built as independent, loosely coupled services. Each service handles one business function, can be deployed independently, and communicates via APIs. Microservices enable team autonomy and independent scaling but add complexity in networking, observability, and consistency.
O-R — Observability to Region
Observability: The ability to understand a system's internal state from its external outputs. The three pillars of observability: logs (event records), metrics (numerical measurements), and traces (request flow across services). Tools include Datadog, Grafana, New Relic, and AWS CloudWatch. Object Storage: Scalable storage for unstructured data (files, images, backups). S3 (AWS), Cloud Storage (GCP), and Blob Storage (Azure) provide virtually unlimited storage at low cost. Region: A geographic area containing one or more data centers (availability zones). Choose regions based on latency to users, compliance requirements, and service availability. Major cloud providers operate 30-60+ regions worldwide. Multi-region deployments provide disaster recovery and global low latency.
S — Serverless to SLA
Serverless: A cloud execution model where the provider manages all infrastructure and you only pay for actual usage. Serverless includes FaaS (Lambda), managed databases (DynamoDB, Firestore), and managed queues (SQS). Benefits: zero infrastructure management, automatic scaling, pay-per-use pricing. Drawbacks: cold starts (latency on first request), vendor lock-in, debugging complexity. Service Mesh: An infrastructure layer that manages service-to-service communication in microservices. Istio, Linkerd, and Consul provide traffic management, security (mTLS), and observability between services. SLA (Service Level Agreement): A commitment from a cloud provider guaranteeing uptime and performance. AWS, GCP, and Azure offer 99.95-99.99% uptime SLAs for most services. SLA breaches typically result in service credits, not cash refunds.
T-V — Terraform to VPC
Terraform: HashiCorp's open-source IaC tool for provisioning cloud infrastructure across any provider. Terraform uses a declarative language (HCL) to define desired state, then creates/modifies/deletes resources to match. Terraform state tracks what resources exist and their configurations. Twelve-Factor App: A methodology for building cloud-native applications with twelve principles including: codebase in version control, explicit dependencies, config in environment variables, stateless processes, and disposable instances. VPC (Virtual Private Cloud): An isolated virtual network within a cloud provider. VPCs contain subnets (public and private), route tables, security groups (firewalls), and internet gateways. VPC peering connects multiple VPCs. VPNs connect VPCs to on-premise networks.