The thesis paper shows the development of a responsive web site designed using HTML, CSS and JS technology. The web site is created as a video library platform, which contains textual and audiovisual information. This work contains thematic units that describe what is needed and everything that is used to create the look and functionality of a video library, and the difference between WordPress and MODX CMS. The video library is connected to the Kaltura Media server, which has it's own player for audiovisual information found on the video library. Kaltura is a platform that allows you to create your own players, build video platforms in the form of youtube, and set up AV content through their media server, which then allows you to view the AV content. This thesis work uses this platform so that the content placed on the Kaltura media server can be shown on the web pages through a specific plugin or code. Video users can read content and view various AV content of informative and entertaining character. The video library users are divided into 3 groups. The first level of the group are ordinary users who use the platform in the form of browsing and consuming AV content of the video library which is controlled by and created by the second level group of users. The second level user group are moderators whose task is to maintain the content of the video library. The third and last level of the group are administrators who have the task of maintaining the system and system files in order to achieve better optimization and user experience of the video library. Digitalization, or democratization of the media, acted in such a way that the creation and publication of audiovisual content became accessible to almost everyone with an internet connection. Streaming AV services are gaining in popularity, and their potential in the marketing-commercial aspect is immense. Streaming platforms or online video libraries gain their popularity thanks to the direct streaming of the desired AV content without a time delay where the user does not have to wait for his chosen AV content. The quality of streaming services on each streaming platform, i.e. the online video library depends on the quality of the Internet connection of the users and the media server of the service server where the AV content is located.