The sendMailTemplateAttachment parameter allows you to use a template with an attachment. The content is added to the email as a MIME attachment.
The purpose of a sendMail template is to allow for intricate and formatted emails using HTML. A template is an HTML file, which contains one or more replacement tokens to embed workflow-specific data into the body of the email. This information might include an account number, customer name, or phone number.
Each token is marked by using the $ symbol, and followed by the number of the token. For example, $1 is the first token, $2 is the second token, and so on. An array of string values (the templateVals parameter) is passed from the workflow and its contents are used to replace the tokens in the template.
To attach the template to a workflow
To verify that the template is attached to a workflow