PGF and TikZ are open source graphic programming languages used for creating graphics and diagrams. It is based on the popular TeX typesetting system and is used by many scientific and technical journals to create figures, charts, and diagrams. PGF stands for Portable Graphics Format, and TikZ stands for TikZ ist kein Zeichenprogramm (TikZ is not a drawing program). PGF and TikZ are very powerful tools that are used to create complex graphics and diagrams. The languages are simple to learn, but the resulting graphics can be very sophisticated and professional-looking. PGF and TikZ can be used to create everything from simple bar graphs and pie charts to intricate illustrations and diagrams. They are also popular for creating scientific visualizations, such as fractals, as well as for creating flowcharts, mind maps, and data visualizations. PGF and TikZ can be used in a variety of contexts, from scientific journal articles to presentations, posters, and even websites.
It is difficult to incorporate the mathematical format LaTeX, which is the main reason why many use PGF / TikZ, and I think LibreOffice - Draw is also more difficult to use to make true vector graphics.
Discontinued No new versions since 2011. The latest version, 0.97.2, can still be downloaded from the official website.