Imaging is a critical technique in biology—from identifying cancerous cells in biopsies to observing how immune cells like macrophages hunt down and destroy pathogens. Traditionally, distinguishing and labeling individual cells in images and videos has been an arduous task done by hand. Now, an interdisciplinary team of Caltech researchers has developed an artificial intelligence algorithm to identify cells in images for a wide variety of biological applications. The new tool, called CellSAM (