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What is automated testing?

Automated testing is code that checks your other code works correctly, run automatically instead of by hand. Tests confirm that features do what they should and keep doing so after changes. They catch bugs before users do and make it safe to change code without breaking things you forgot about.

There are levels: unit tests check small pieces, integration tests check parts working together, and end-to-end tests simulate a real user flow. A healthy project has a mix, weighted toward fast, focused tests.

The benefit is confidence to move fast. With good tests, a team can refactor and add features knowing a break will be caught immediately. Skipping tests feels faster at first, then gets slower and riskier as the codebase grows and every change becomes a gamble.

Updated July 2026

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What is CI/CD?
CI/CD (continuous integration and continuous delivery) is an automated pipeline that checks and ships code. When a developer pushes a change, CI automatically runs tests and checks to catch problems, and CD automatically deploys the change if it passes. It makes releasing software faster, safer, and routine.
What is a linter and a formatter?
A linter automatically checks code for likely mistakes, risky patterns, and style issues as you write. A formatter automatically arranges code consistently (spacing, indentation, quotes). Together they catch small errors early and keep a codebase uniform, so it reads as if one person wrote it.
What is Git?
Git is the standard tool for tracking changes to code. It records every edit as a snapshot, so a team can work on the same project at once, see who changed what, and roll back to any earlier version. Almost every software project uses it. Working without it is like writing without an undo button.
What is the difference between Git and GitHub?
Git is the tool that tracks code changes on your computer. GitHub is an online service that hosts Git projects so teams can store, share, and collaborate on them in the cloud. Git is the technology, GitHub is a popular place to keep and work on Git projects. GitLab and Bitbucket are alternatives.
What is version control, and why does it matter?
Version control is the practice of recording every change to a project over time, so you can see its history, work in parallel, and undo mistakes. Git is the dominant version-control system. It matters because it turns code from a fragile single copy into a safe, traceable, collaborative thing.
What is a package manager (npm, pip)?
A package manager installs and manages the outside code libraries a project depends on. npm handles JavaScript packages, pip handles Python, and most languages have one. Instead of manually downloading and updating libraries, you list what you need and the package manager fetches the right versions.

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What is automated testing?

What is CI/CD?

What is a linter and a formatter?

What is Git?

What is the difference between Git and GitHub?

What is version control, and why does it matter?

What is a package manager (npm, pip)?

Want this built, not just explained?