Browsers have become the most common communication channel. We spend hours using them to get news and communicate with friends, far more time than communicating face-to face. WWW-based communication and content-creation for www will be the most common job in future work life for students specializing in software engineering. We expect our screens to be colorful and animated, thus students should understand technologies, which are used for e.g. for painting jumping Mario to screen. But massive flow of new software engineering ideas, technologies and frameworks which appear in all-increasing temp tend to make students passive receivers of descriptions of new menus and commands without giving them any possibility to investigate and understand, what is behind these menus and commands, killing their natural curiosity. There should be time to experiment, compare formats, technologies and investigate their relations. In the presentation are described experiments used for investigating, how different formats for describing animation in HTML5 document influence animation rendering speed.