GanttProject is free Java based, project management software that runs on the Windows, Linux and Mac OS X systems. Developed by Dmitry Barashev, Alexandre Thomas
License: Open Source
LiquidPlanner is a comprehensive project management tool with advanced features like time tracking, resource management, and reporting, making it suitable for larger teams and complex projects. In contrast, GanttProject is a simpler, free tool that excels in basic Gantt chart functionalities but lacks many advanced features, making it ideal for small projects and beginners.