Svelte can output web components, which is:
a suite of different technologies allowing you to create reusable custom elements — with their functionality encapsulated away from the rest of your code — and utilize them in your web apps.
This lets you write something like this in an app to render a component created with Svelte:
...
<head>
<script defer src="/bundle.js"></script>
</head>
<body>
<cool-component></cool-component>
</body>
...
Instructions can be found in the Svelte API documentation and a walkthrough is available in this video tutorial:
This is an alternative to what most Svelte users export, which are Svelte components rendered by specifying the target element when instantiating the component.
import Component from "./Component.svelte";
const app = new Component({
target: document.querySelectorAll("#svelte-component"),
props: {},
});