E-Mail Marketing is a part of Online-Marketing and helps to approach customers and to enlarge and tighten existing customer contacts. The main task of this section is to send E-Mails. This can be divided into one-to-one-communication and one-to-many-communication. The former describes the classic distribution of an E-mail to a specific person. The second option, one-to-many-communication, describes the distribution of an E-mail to as many people as wanted. The extreme form of this method is the so called Spam, which can bother customers and can also lead to an economic loss, e.g. by a damage of the reputation through using Spam E-Mails.