Continuous Integration
In plain terms
Frequently merging code changes and automatically testing them.
Going deeper
CI has developers integrate work into a shared branch often, with automated builds and tests running on each change to catch problems early. It keeps the codebase healthy and integration painless.
Under the hood
Relies on a fast, reliable automated test suite and a single source of truth; flaky tests and long builds erode its value, so caching and parallelism matter.
Examples
GitHub Actions, Jenkins, GitLab CI, CircleCI running build+test on each PR.
Think of it like...
Like a potluck where everyone tastes each dish as it arrives, instead of discovering at the end that nothing goes together.