> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ntop.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Before We Begin: Custom Blocks

export const YouTubeVideo = ({src, title, caption}) => {
  return <Frame caption={caption}>
      <iframe className="w-full aspect-video rounded-xl" src={`https://www.youtube.com/embed/${src}`} title={title} allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowFullScreen></iframe>
    </Frame>;
};

<YouTubeVideo src="MfCSsGHqDZM" />

In this course, we will:

* Understand the key areas for defining a custom block.
* Explore how to use list processing.
* Learn how to implement a custom block into a workflow.