This bachelor thesis deals with current methods used by plagiarists for creating text documents. The thesis is mainly focused on documents in the Czech language. Therefore, there was chosen Czech software for the application part. There are defined several basic concepts in the introduction. These concepts are an important pillar for the understanding of the topic. The theoretical part is based on several currently used plagiarism methods. In addition to the definition of these types, there are also presented some examples of them. Further, there are presented current tools for detecting plagiarism. The thesis is focused on Czech and foreign detection solutions. The aim of the application part is to determine to what extent the software too...