Focus stacking is a technique that allows you to create images with a deeper depth of field than what your camera can achieve in a single shot. It involves taking multiple photos of the same scene, each with a different focus point, and then blending them together in a software program such as Photoshop or Lightroom. By doing this, you can ensure that every part of your image is sharp and in focus, from the foreground to the background. Focus stacking is especially useful for macro photography, product photography, and landscape photography, where you want to capture fine details and textures across a wide range of distances.