Algodoo

Algodoo is an interactive physics sandbox that lets users draw objects and then observe how they behave under forces such as gravity, friction, fluid dynamics, and optics. The program provides simple drawing tools, color coding, and visual aids like graphs to help users construct and explore mechanical, hydraulic, and optical systems in real time.

It is aimed at educators, students, hobbyists, and anyone interested in experimenting with physical concepts, offering a hands‑on way to build simulations, test ideas, and create animated scenes without requiring programming knowledge. The software runs on macOS (including Apple Silicon) and is available for free, with additional platforms such as Windows and iPad mentioned in the source.

What distinguishes Algodoo is its focus on intuitive, click‑and‑drag interaction combined with visual feedback, allowing users to tilt, shake, or apply forces to their creations and instantly see the resulting motion and energy changes. This makes it a practical tool for STEM learning, home schooling, and informal experimentation.