Backend
The server-side code and infrastructure that powers a website or application, handling data processing, storage, and business logic invisibly.
Definition
The backend encompasses all server-side operations: databases, servers, APIs, and application logic that users don't directly see. It handles data processing, storage, authentication, and business logic that powers what users experience on the frontend.
Backend technologies include languages like Python, Node.js, and Ruby, along with databases like PostgreSQL and MongoDB.
Why It Matters
The backend determines application performance, scalability, and security. A poorly architected backend creates technical debt that compounds as products grow.
Understanding backend constraints helps designers and product managers make informed decisions about feature complexity.
Examples in Practice
A backend team builds APIs that let the mobile app retrieve user data and process transactions.
Backend optimization reduces page load times by improving database queries and implementing caching.
A security audit focuses on backend authentication systems to prevent unauthorized data access.