Add to ORKGDiploma thesis deals with the influence of the selected attributes of e-mails. Based on the previous research and results they should change the behaviour of the recipients. In the theoretical part author will explain the e-mail and its issues as one of the tools used in new media. The closer focus will be given to the optimalization of e-mails as it will be used for the basis of research. The practical part identifies what features of content and design of email marketing significantly influence the level of public engagement. The methodological basis of research is quantitative method. To test the results of hypotheses a technique of A/B testing will be used. The test focused on selected features will be sent and monitored on the sample o...