Transactional e-mails are informational e-mails sent by Magento. They are used, for instance, to let your visitors know about their placed orders, send password reminder e-mails, and to send product recommendations. Besides informing customers, they are also used to send store administrators updates such as low stock notifications. In this section we will only focus on the e-mails intended for customers.
In general, there are three things store owners want to change in transactional e-mails:
The logo used in the e-mails
The text inside the e-mails
The layout of the e-mails
The first and second should always be done as otherwise your store will be sending e-mails to your customers with Magento's logo and default texts. However, you can skip the third (recommended) as Magento's default layout for the transactional mails is usually fine to start with. If you do want to change the layout of the transactional mails, we suggest contacting somebody who has experience with...