An atomic force microscope scans a nanometre-sharp tip across a surface and infers topography not from light or tunneling current, but from mechanical force: van der Waals attraction and short-range repulsion between tip and sample bend a flexible cantilever by fractions of a nanometre, and a laser bouncing off the cantilever's back onto a photodetector converts that bend into a signal. This simulator lets you scan a sample in contact or tapping mode and watch the reconstructed topographic image build row by row, or switch to force-curve mode to drive the tip toward a fixed point and trace the classic approach/retract hysteresis loop — the snap-to-contact and adhesion pull-off used to measure a surface's stiffness and stickiness.