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apps/website/docs/getting-started/usage.md

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+# Usage
+
+Learn the basics of using ffmpeg.wasm.
+
+:::note
+It is recommended to read [introduction](/docs/intro) to fully understand the
+rationale.
+:::
+
+## Basic
+
+Converting an AVI video to a MP4 video:
+
+```js
+import { FFmpeg } from "@ffmpeg/ffmpeg";
+import { fetchFile } from "@ffmpeg/util";
+
+const videoURL = "https://github.com/ffmpegwasm/testdata/raw/master/video-15s.avi";
+
+(async () => {
+    const ffmpeg = new FFmpeg();
+    // Create a web worker and the worker loads WebAssembly code.
+    await ffmpeg.load();
+    // Write a video file to FS.
+    await ffmpeg.writeFile("input.avi", await fetchFile(videoURL));
+    // Execute ffmpeg command.
+    await ffmpeg.exec(["-i", "input.avi", "output.mp4"]);
+    // Read the output video file from FS, the output file is a Uint8Array typed
+    // array.
+    const data = await ffmpeg.readFile("output.mp4");
+})();
+```