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DevOps Glossary

Networking

DNS (Domain Name System)

The hierarchical, decentralized database that translates human-readable domain names (like example.com) into IP addresses (like 192.0.2.1).

Security

SSL/TLS

Cryptographic protocols designed to provide communications security over a computer network. TLS is the modern successor to SSL, encrypting data between client and server.

Containers

Docker

A platform designed to build, ship, and run applications inside isolated lightweight environments called containers, resolving the "works on my machine" problem.

Infrastructure

Nginx

A high-performance web server, reverse proxy, and load balancer. Commonly used as the frontend gateway to distribute client traffic to backend app processes.

Infrastructure

Reverse Proxy

A server that sits in front of backend applications and forwards client requests to those applications. Used for security, SSL termination, and load balancing.

Automation

CI/CD

Continuous Integration (CI) automates the testing and building of code. Continuous Deployment (CD) automates the shipping of build artifacts to production servers.

Security

OIDC (OpenID Connect)

An authentication layer on top of OAuth 2.0. In CI/CD, it allows tools like GitHub Actions to request short-lived temporary AWS credentials without storing long-lived access keys.

Infrastructure

Cloudflare

A global network provider offering DNS, CDN caching, Web Application Firewall (WAF), and DDoS protection. It sits as a proxy between clients and web hosts.

Security

WAF (Web Application Firewall)

A specialized firewall that monitors, filters, and blocks HTTP traffic to and from a web application, protecting against attacks like SQL injection and cross-site scripting (XSS).

SEO

Technical SEO

Optimizations made to a website's infrastructure to help search engine crawlers find, parse, and index pages more efficiently.

Performance

Core Web Vitals

Google's standardized metrics for measuring user experience: LCP (loading speed), CLS (visual stability), and INP (responsiveness to user inputs).

Performance

LCP (Largest Contentful Paint)

A Core Web Vital metric measuring when the largest text block or image on a page becomes visible to the user during load. Good is under 2.5 seconds.

Performance

CLS (Cumulative Layout Shift)

A Core Web Vital metric measuring how much elements shift around while a page is rendering. Lower layout shift is better. Good is under 0.1.

Performance

INP (Interaction to Next Paint)

A Core Web Vital metric measuring the latency of all user interactions (clicks, taps, keyboard inputs) on a page. Good is under 200 milliseconds.

Observability

Sentry

An application monitoring platform that captures unhandled exceptions and crashes in real time, providing developers with detailed stack traces and user context.

Observability

Uptime Monitoring

The process of periodically pinging an endpoint (typically /health) to ensure the system is operational and responding to HTTP requests.

Security

OWASP Top 10

A standard awareness document for developers representing a broad consensus on the most critical security risks to web applications.

Security

CORS

A mechanism that uses additional HTTP headers to tell browsers to give a web application running at one origin permission to access selected resources from a different origin.

Security

CSP (Content Security Policy)

An HTTP header that allows site operators to restrict the resources (such as JavaScript, CSS, Images) that the browser is allowed to load for a given page, mitigating XSS.

Email

SPF, DKIM, DMARC

Email authentication standards that prove an email is actually sent by the owner of the sending domain, preventing spoofing and ensuring inbox deliverability.

Infrastructure

Redis

An open-source, in-memory data structure store used as a database, cache, message broker, and streaming engine.

Infrastructure

RabbitMQ

An open-source message broker that supports multiple messaging protocols, commonly used to process background jobs asynchronously.

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