Multisim 9 is the world's leading electronics circuit design, analysis and simulation tool. Our easy-to-use software enables you to quickly design and analyze analog, digital and mixed-mode circuits, just like the pros! The powerful and interactive SPICE simulation engine ""runs"" your circuit and allows you to explore its inner workings. Only Multisim allws you to modify your circuits while simulating, and instantly see the results on intuitive virtual instruments.