The sent e-mail message (including attachments) looks like a collection of illogical characters and can only be read by the recipient who has a unique key to decrypt it.
There are several ways to send an encrypted email using Talkey. You can use the Talkey application or you can use the Talkey add-on in your daily email client for easy encryption. The third way to send an encrypted message is to use the sharing function, through third-party applications.