IT & cloud glossary
Plain-English definitions of the networking, cloud, security and DevOps terms engineers meet every day.
- API (Application Programming Interface)
- A contract that lets two pieces of software talk to each other — usually over HTTP using JSON.
- BGP (Border Gateway Protocol)
- The routing protocol that holds the internet together by exchanging reachability information between autonomous systems.
- CIDR (Classless Inter-Domain Routing)
- Notation like 10.0.0.0/24 used to express IP address ranges and subnet masks compactly.
- Container
- A lightweight, isolated process bundled with its dependencies — the unit Docker and Kubernetes manage.
- DDoS (Distributed Denial of Service)
- An attack where many machines flood a target with traffic to make it unavailable.
- DNS (Domain Name System)
- The phone book of the internet — translates names like example.com into IP addresses.
- Edge Function
- Server code executed close to the user on a CDN edge node, reducing latency.
- FIDO2 / Passkey
- Phishing-resistant authentication standard that replaces passwords with a public-key credential bound to the origin.
- GitOps
- Operating model where Git is the single source of truth for infrastructure and application config.
- IaC (Infrastructure as Code)
- Defining infrastructure (servers, networks, DNS) in version-controlled files using tools like Terraform.
- JWT (JSON Web Token)
- A signed, base64-encoded JSON payload commonly used for stateless API authentication.
- Kubernetes
- Open-source platform that orchestrates containers across a cluster of machines.
- LLM (Large Language Model)
- A neural network trained on huge text corpora to generate human-like text — e.g. GPT, Gemini, Claude.
- MFA (Multi-Factor Authentication)
- Login security that requires something you know plus something you have or are.
- NAT (Network Address Translation)
- Technique that maps many private IP addresses to one public address — the reason your home network works.
- OAuth 2.1
- Modern delegated authorization protocol used by Sign-in-with-Google, GitHub, etc.
- Pod
- Smallest deployable unit in Kubernetes — one or more containers sharing network and storage.
- RBAC (Role-Based Access Control)
- Authorization model that assigns permissions to roles, then assigns roles to users.
- SaaS (Software as a Service)
- Software delivered over the internet on a subscription basis — like Stackvora.tech.
- SSO (Single Sign-On)
- One login that grants access to many applications — usually via SAML or OIDC.
- TLS (Transport Layer Security)
- The encryption protocol that puts the S in HTTPS.
- VLAN (Virtual LAN)
- Logical segmentation of a physical network — used to separate user, voice, and management traffic.
- VPN (Virtual Private Network)
- Encrypted tunnel that extends a private network across the internet.
- WAF (Web Application Firewall)
- Filter that inspects HTTP traffic for application-layer attacks like SQL injection and XSS.
- Zero Trust
- Security model that never assumes trust — every request is authenticated, authorized, and encrypted.