Let me introduce a nice, easy to use, free and open software made to draw diagrams in seconds. Support layers, can group items for easier work, and have a huge palette with predefined symbols for various type of diagrams. It's called Dia, and works fine on Windows, Linux or Mac OS.
Some useful palettes:
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The must have software for programmers and engineers, moreover good tool for other people too!
Some useful palettes:
- Electric, Circuits
- ER, Database, UML
- Cisco, Network
- Flowchart
- Engineering diagrams [Chemical-, and Civil engineering, Cybernetics]
Download
The must have software for programmers and engineers, moreover good tool for other people too!