Dia Diagram Editor is a software application that is capable of creating diagrams, graphs, charts etc. It supports UML diagrams, flowcharts, entity-relationship diagrams, network diagrams and more.
Dia functions like Microsoft Visio. It can be used to draw many different kinds of diagrams. It is also capable of adding support for new shapes by writing simple XML files, using a subset of SVG to draw the shape. It can load and save diagrams to a custom XML format , can export diagrams to a number of formats, including EPS, SVG, XFIG, WMF and PNG, and can print diagrams even those that span to multiple pages.