Dia is an editor for semi-structured diagrams like UML, ER, flowcharts etc, somewhat inspired by Visio. Dia supports a variety of shapes, and can be extended by the user. It imports several formats, including SVG, DXF, and FIG, and exports even more, including CGM, ESP, MP, WMF. There are also several tools available for automatically generating diagrams or generating source code or databases from diagrams. Dia does not attempt to verify that the diagrams adhere to standards, but gives the user the freedom to illustrate ideas in different ways.