DevOps & Cloud Glossary

A

API Gateway

A single entry point that manages, secures, and routes requests to your backend services or APIs.

Autoscaling

Automatically adding or removing compute capacity based on real-time demand, so you pay for what you actually use.

Availability Zone

An isolated location within a cloud region with its own power and networking, used so a failure in one zone doesn't take down your whole system.

B

Blue/Green Deployment

A release strategy that runs two identical environments and only sends traffic to the new one once it's verified healthy, so a bad release can be rolled back instantly.

C

CI/CD

Continuous Integration and Continuous Delivery: automatically testing and shipping every code change instead of doing it by hand.

Cloud Migration

Moving applications, data, and workloads from on-premises servers, or from one cloud provider to another, ideally without downtime.

Compliance Audit

An independent review that checks whether your infrastructure and processes actually meet a framework's requirements, like SOC 2 or HIPAA.

Container

A lightweight, self-contained package that bundles an application with everything it needs to run, so it behaves the same on any machine.

Container Orchestration

Software, most commonly Kubernetes, that automatically deploys, scales, and manages containers across a cluster of machines.

Cost Optimization (FinOps)

The ongoing practice of right-sizing cloud resources, eliminating waste, and making spend visible, rather than a one-time cleanup.

D

DDoS

Distributed Denial-of-Service: an attack that floods a system with traffic from many sources at once, trying to knock it offline.

DevOps

The practice of combining development and operations so software gets built, tested, and released faster and more reliably.

DevSecOps

Building security checks directly into the development and deployment pipeline, instead of testing for problems only at the very end.

Disaster Recovery

A tested plan for restoring systems and data after an outage or failure, not just a backup that's never actually been checked.

Docker

The most widely used tool for building and running containers.

Drift (Configuration Drift)

When a live environment's actual settings quietly diverge from what's defined in code, usually from manual changes nobody tracked.

G

GitOps

Managing infrastructure and deployments by describing the desired state in Git, so every change is reviewed, versioned, and automatically applied.

GPU Infrastructure

Servers built around graphics processing units, used to train and run AI and machine learning models efficiently.

H

Helm

A package manager for Kubernetes that bundles related resources into a single, reusable, versioned unit called a chart.

HIPAA

A US law setting requirements for protecting patient health information, relevant to any company handling healthcare data.

I

IAM (Identity and Access Management)

The system that controls who, or what, can access which resources, and what they're allowed to do once they're in.

Immutable Infrastructure

Servers and environments that are never modified after deployment; instead of patching in place, you replace them with a new version.

Infrastructure as Code (IaC)

Defining servers, networks, and cloud resources in code instead of clicking through a console, so environments are consistent and reviewable.

ISO 27001

An international standard for information security management, often required by enterprise customers before they'll sign a contract.

K

Kubernetes

An open-source system for automating the deployment, scaling, and management of containerized applications.

L

Least Privilege

A security principle: give every person and system only the access they actually need, nothing more.

Load Balancer

A component that spreads incoming traffic across multiple servers, so no single one gets overwhelmed and the system stays up if one fails.

Logging

Recording what a system did, and when, so you can investigate what happened after the fact.

M

Managed Service

Infrastructure or software that a provider runs and maintains on your behalf, so your team doesn't have to.

Microservices

An architecture that splits an application into small, independently deployable services, instead of one large program.

MLOps

The practices and tooling for reliably building, deploying, and monitoring machine learning models in production.

Multi-Cloud

Running workloads across more than one cloud provider, for resilience, pricing leverage, or avoiding lock-in.

O

Observability

The combination of metrics, logs, and traces that lets you understand what's actually happening inside a running system.

On-Premises (On-Prem)

Infrastructure that runs on hardware a company owns and operates itself, rather than in the cloud.

P

PCI DSS

A security standard required for any business that stores, processes, or transmits credit card data.

Penetration Testing

A simulated, authorized attack on your systems to find exploitable vulnerabilities before a real attacker does.

R

Reserved Instances

Cloud capacity you commit to paying for over a fixed term, usually one to three years, in exchange for a lower price than pay-as-you-go.

Right-Sizing

Matching the size of a server or database to what it actually needs, instead of what was guessed when it was first set up.

Rollback

Reverting a deployment back to its last known-good version, usually automatically, when a release causes problems.

RTO & RPO

Recovery Time Objective (how long you can be down) and Recovery Point Objective (how much data you can afford to lose), the two numbers that define a disaster recovery plan.

S

Serverless

Running code without provisioning or managing servers yourself; the cloud provider handles the infrastructure and you pay only for what runs.

Service Mesh

A dedicated infrastructure layer that manages how services talk to each other, handling routing, security, and observability between them.

SLA / SLO / SLI

The agreement you promise a customer (SLA), the internal target you aim for (SLO), and the actual metric you measure (SLI), for things like uptime.

SOC 2

An audit that verifies a company's controls around security, availability, and data handling, commonly requested by B2B and enterprise customers.

Spot Instances

Spare cloud capacity sold at a steep discount, with the tradeoff that it can be reclaimed on short notice, best for flexible workloads.

SRE (Site Reliability Engineering)

An engineering discipline that applies software practices to operations, aiming to keep systems reliable at scale.

T

Terraform

An open-source infrastructure-as-code tool that lets you define cloud resources in a simple configuration language and apply them consistently.

Tracing

Following a single request as it moves through every service it touches, to pinpoint exactly where time is spent or something failed.

V

VPC (Virtual Private Cloud)

An isolated, private section of a cloud provider's network where you control the IP ranges, subnets, and routing.

Vulnerability Assessment

A scan that identifies known security weaknesses across your systems and ranks them by severity.

W

WAF (Web Application Firewall)

A filter that sits in front of a web application and blocks common attacks before they ever reach it.

Z

Zero Trust

A security model that never automatically trusts a request, inside or outside the network, and instead verifies every single one.