Codeacademy doesn't overwhelm beginners with information. It gives bite-sized information, the bare minimum needed to finish a task and get to the next one. As the course progresses, it slowly fills in background information.
Right from the start, users write code. They start small in an environment that has constant feedback and gradually progress to more complex concepts. Users can see code results instantly, giving great feedback.
The content of the lessons is aimed very much at people just starting to learn how to code. This is perfect for beginners but if you want to use Codecademy to refresh your knowledge the lessons are not designed to be quickly done.
Codecademy is great for providing a hands-on approach, but there is a lack of context regarding how to start a project in real life. While users may learn how to code using Codecademy's interface, they may not have any idea how to code independently.