It would be impractical to put your entire app in a single component. Instead, we can import components from other files and then use them as though we were including elements.
We now present you 2 files in the editor on the right (upper bar) to click on, App.svelte and Nested.svelte.
Each .svelte file holds a component that is a reusable self-contained block of code that encapsulates HTML, CSS, and JavaScript that belong together.
Let's add a <script> tag to App.svelte that imports the file (our component) Nested.svelte into our app...
Notice that even though Nested.svelte has a <p> element, the styles from App.svelte don't leak in.
Also notice that the component name Nested is capitalised. This convention has been adopted to allow us to differentiate between user-defined components and regular HTML tags.