For example, it`s necessary to pay attention to the target button design that allows the customer to perform a certain action, such as to go to the product page with the possibility of quick purchase. This button should be noticeable and have capacious text of several words so that the customer understand what will happen in case you press this button. Personified letters have information that can interest a particular customer (for example, informing that a product purchased earlier is currently under discount, etc.) has a very positive effect. The development of the HTML letters design may differ depending on their purpose. There are newsletters that inform clients about current promotional offers or updates on the news from the life of the company (new store or representative offices opening) or that can be letters in the form of an online survey to increase the quality of the services, advertising, and other informational messages.