Below is the list of email templates that can be created in Salesforce:
Text: Text templates can be created or changed by all the users in the organization.
HTML with Letterhead: Admins and users who have ‘Edit HTML Templates’ can create this type of template based on a letterhead.
Custom HTML: It is an extension of the previous one. Admins and users having ‘Edit HTML Templates’ can create custom HTML templates even without the need for a letterhead.
Visualforce: Admins and developers can create this template using Visualforce. It provides advanced functionalities like merging recipient’s data from multiple records.