The world can be a busy place. Walking down a crowded street, there is a sea of faces in front of you. Look in a shop window, and there is an array of objects for sale. Look up in the sky, and several ...

You often have to make quick judgments about the number of objects you encounter in the world. You might see a group of people walking toward you. It is useful to know whether there are roughly five, ...

The colors in a photograph convey a mood, but the existing colors in an image don’t always jive with the rest of the image or give you the mood that you’re looking for. Maybe that neon outfit is ...