The diploma thesis analyzes posts that are produced by three online Czech news websites - Aktuálně.cz, iDnes.cz and Novinky.cz. The lingustic analysis is based on the five linguistic levels - orthography, syntax, lexicology, morphology and stylistics. The news writing style and its characteristics are described in the theoretical part. It is accompanied by the description of the electronic communication phenomena. The key theoretical knowledge about changes in the Czech language used on the Internet is summarized. Chapter focused on Facebook development and its specific features is also included. The results of the analysis show two main tendencies in Czech language used on Facebook by online news websites. Firstly, language originality was used to capture user attention in Facebook feed. Secondly, the economy of language, shortness and conciseness in Facebook posts were identified. Results reveal the high number of spelling errors, high frequency of elliptical and condensed sentences without redundant phrases. The sentences were often replaced by nominal equivalents or fragments without predicates. Neologisms and colloquial Czech are considerably present in the text. All posts contain a significant graphical section.