Modern diagram editor , Easily draw flowcharts, DFDs, ERDs, use case diagrams and etc. It is an open source alternative to visio
A complete tutorial about the most famous diagram type that is flowcharts . This tutorial explains the main concepts of flowchart diagrams using programming examples.
Complete guide about flowcharts , this article is a perfect flowchart tutorial with samples about this kind of diagram
This article discusses important factors in beauty and readablity of diagrams.
An overview of famous diagram types such as flowcharts, pie charts, bar charts, concept map, mind map and etc.