Right now, the collection of habits and the business logic for adding a habit are in the component. This works fine for how small our app is right now, but what if we need to access the collection of habits in another component? Or what if we need to add a habit somewhere else? We'd either have to duplicate code or come up with convoluted ways of passing data through inputs and outputs. This is what services are for in Angular. Services let us store data and logic in a class that we can reuse anywhere in our application.