Lesson 6: Testing, Deployment, and Security

Testing ensures an application works as intended. Common types include unit testing (checking individual functions or components) and integration testing (checking combined parts). For example, a unit test might verify that a function correctly adds two numbers. Automated tests (written in code) are standard practice. In exams, you might have to identify which type of testing is needed or explain how testing catches bugs before release.

Deployment is releasing an application to users (for example, uploading a website or submitting an app to a store). DevOps is the practice of combining development and operations, often using continuous integration/continuous deployment (CI/CD) tools. This means whenever new code is written, automated processes test and deploy it. For instance, after committing code, a CI/CD system can run tests and update the live app without manual steps. Questions may cover the concept of a deployment pipeline or why automated deployment reduces errors.