The Send Note plugin enables users to easily share notes between Obsidian vaults via AWS S3. Notes are uploaded to a user-provided S3 bucket and shared using a URL, which is embedded in the note's YAML frontmatter. The plugin ensures security by encrypting the content of the notes, allowing only the sender and recipient to access the information. Users can also delete the notes directly from S3 via Obsidian. The plugin supports additional functionalities like setting up custom S3 configurations and integrating with other tools, such as the s3-image-uploader plugin, for seamless media file sharing. This plugin offers an efficient and secure way to collaborate and share notes across different users while maintaining privacy.