[Authentication vs Authorization](atomicglue.co/glossary/authentication-vs-authorization-backend) — Authentication verifies who you are. Authorization verifies what you are allowed to do. They are two distinct security concepts that are often confused. Authentication always comes before authorization.
[Caching (Redis)](atomicglue.co/glossary/caching-redis) — Caching is the technique of storing frequently accessed data in a fast, temporary storage layer to serve future requests faster. Redis is the most popular in-memory data store used for caching, providing sub-millisecond response times.
[Cold Start](atomicglue.co/glossary/cold-start-serverless) — A cold start is the delay that occurs when a serverless function is invoked after being idle. The cloud provider must provision resources and initialize the runtime before executing the code.
[CORS](atomicglue.co/glossary/cors-backend) — CORS (Cross-Origin Resource Sharing) is a browser security mechanism that controls which web pages can request resources from a different origin. It uses HTTP headers to define allowed origins, methods, and headers for cross-origin requests.
[CSP](atomicglue.co/glossary/csp-backend) — Content Security Policy (CSP) is a browser security standard that prevents cross-site scripting (XSS), clickjacking, and other code injection attacks by controlling which resources a page can load and execute.
[Database](atomicglue.co/glossary/database) — A database is an organized collection of structured data stored and accessed electronically. It provides persistent storage, efficient retrieval, concurrent access, and data integrity through a Database Management System (DBMS).
[Edge Functions](atomicglue.co/glossary/edge-functions) — Edge functions are serverless functions that run at the network edge, in CDN nodes geographically close to users, rather than in a single centralized region. They minimize latency by executing code as close to the user as possible.
[Express.js](atomicglue.co/glossary/express-js) — Express.js is a minimal, unopinionated web application framework for Node.js that provides a thin layer of routing, middleware, and HTTP utilities. It is the most widely used Node.js web framework.
[GraphQL](atomicglue.co/glossary/graphql) — GraphQL is a query language and runtime for APIs, developed by Meta (Facebook), that lets clients request exactly the data they need in a single request. It provides a strongly typed schema and real-time subscriptions.
[JWT](atomicglue.co/glossary/jwt-backend) — JWT (JSON Web Token) is a compact, URL-safe token format for representing claims between two parties. It is commonly used for stateless authentication and secure information exchange in web applications.
[Node.js](atomicglue.co/glossary/node-js) — Node.js is an open-source, cross-platform JavaScript runtime built on Chrome's V8 engine that executes JavaScript outside the browser. It is the standard runtime for server-side JavaScript development.
[NoSQL](atomicglue.co/glossary/nosql) — NoSQL (Not Only SQL) is a category of database systems that provide flexible, non-tabular data models for specific use cases where relational databases are less optimal. Types include document, key-value, wide-column, and graph databases.
[OAuth 2.0](atomicglue.co/glossary/oauth-2-0) — OAuth 2.0 is an authorization framework that allows third-party applications to obtain limited access to a user's resources without exposing the user's credentials. It is the industry standard for delegated access.
[ORM](atomicglue.co/glossary/orm) — ORM (Object-Relational Mapping) is a technique that lets developers interact with a relational database using object-oriented code instead of writing SQL directly. It maps database tables to classes and rows to objects.
[PHP](atomicglue.co/glossary/php) — PHP is a server-side scripting language designed for web development. It powers a massive portion of the web, including WordPress, and has modernized significantly since PHP 7 with JIT compilation and typed properties.
[Python](atomicglue.co/glossary/python) — Python is a high-level, interpreted programming language known for its readable syntax, extensive standard library, and massive ecosystem. It is one of the most versatile languages, used across web development, data science, automation, and AI.
[REST](atomicglue.co/glossary/rest) — REST (Representational State Transfer) is an architectural style for designing networked applications, primarily APIs. It relies on stateless, resource-oriented communication over HTTP with uniform interface constraints.
[Serverless Functions](atomicglue.co/glossary/serverless-functions) — Serverless functions are single-purpose, event-driven code snippets that run on cloud infrastructure without managing servers. The cloud provider handles scaling, availability, and billing (per-execution).
[Single Sign-On (SSO)](atomicglue.co/glossary/single-sign-on-sso) — Single Sign-On (SSO) is an authentication system that lets users log in once with one set of credentials and gain access to multiple independent applications without re-entering credentials.
[SQL](atomicglue.co/glossary/sql) — SQL (Structured Query Language) is the standard language for managing and querying relational databases. It is used to create, read, update, and delete data in structured tables with defined schemas and relationships.
[Webhook](atomicglue.co/glossary/webhook) — A webhook is an HTTP callback that sends real-time data from one system to another when a specific event occurs. It is a server-to-server push mechanism, the opposite of polling.