Free
CourseLearn TypeScript: Type Narrowing
Gain insights into the runtime behavior of the TypeScript code by narrowing down union types.
Skill level
BeginnerTime to complete
Approx. 1 hoursCertificate of completion
Included with paid plansPrerequisites
None
About this course
Continue your TypeScript learning journey with Learn TypeScript: Type Narrowing. Leverage TypeScript’s type system to gain insights into the runtime behavior of your code by narrowing down what types unions may actually be.
Syllabus
Type Narrowing
Leverage TypeScript’s type system to gain insights into the runtime behavior of your code by narrowing down what union types.
The platform
Hands-on learning
Don’t just watch or read about someone else coding — write your own code live in our online, interactive platform. You’ll even get AI-driven recommendations on what you need to review to help keep you on track.
Meet the creator of the course

Kenny Lin
Web Development Domain Manager at Codecademy Reviews from learners
- The progress I have made since starting to use codecademy is immense! I can study for short periods or long periods at my own convenience - mostly late in the evenings.ChrisCodecademy Learner @ USA
- I felt like I learned months in a week. I love how Codecademy uses learning by practice and gives great challenges to help the learner to understand a new concept and subject.RodrigoCodecademy Learner @ UK
- Brilliant learning experience. Very interactive. Literally a game changer if you're learning on your own.John-AndrewCodecademy Learner @ USA
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Practice Projects
Guided projects that help you solidify the skills and concepts you're learning.Assessments
Auto-graded quizzes and immediate feedback help you reinforce your skills as you learn.Certificate of Completion
Earn a document to prove you've completed a course or path that you can share with your network.