CI vs CD

Continuous Integration (CI) is the practice of merging every developer's code changes into a shared branch frequently, often multiple times a day, with an automated build and test run triggered on every merge. Continuous Delivery and Continuous Deployment (both abbreviated CD) pick up where CI leaves off: they automate getting a validated build out toward, or all the way into, production. The two terms are often said together as CI/CD, but they solve different problems: CI is about catching integration problems early, while CD is about removing manual steps from getting working code released.

A typical CI pipeline triggers on every push: it checks out the code, installs dependencies, compiles or builds the project, and runs the automated test suite, reporting success or failure back to the developer within minutes. Because integration happens so often, when something breaks, it is usually caused by a small, recent change, which makes the cause far easier to find than if branches had diverged for weeks before merging.

Continuous Delivery automates every step up to production but keeps a manual approval gate before the final release, giving a human the chance to decide when code actually goes live. Continuous Deployment goes one step further and removes that manual gate entirely: every change that passes all automated checks is released to production automatically, with no human in the loop. Choosing between the two is a risk and maturity decision, not a technical limitation, since both rely on the same underlying automated pipeline.