Data is everywhere, and more and more data visualizations are being put online. For example, online dashboards have become very popular, not least due to the Corona pandemic. Data visualization or information visualization is the study of (interactive) visual representations of data to enhance human cognition. Humans are much better at interpreting visual representations than they are at reading numbers, so visual representations of data are needed more than ever. When integrating data visualization into a web application, certain aspects have to be considered, both in terms of performance and data security. In this talk I will focus on current data visualization techniques for online data presentation and give an overview of current applications and libraries as well as common pitfalls.