Pareidolia is the ability to find pictures in inanimate objects like rocks, potatoes, linens, the moon, inkblots, and anything else. Most often people will see faces but it can also be whole bodies, animals and cultural icons. You could look at dots of this and that on the wall and find an image represented in them. No one else may see it the same way you do. Overall, it's one way to pass the time while waiting for the bus, doctor, etc. Another form of pareidolia are sounds heard and attributed to mysterious sources, like ghosts. Some ghostly noises could be explained as our own perception of the noise/ sound. What have you seen a face in lately? Think about the idea today and see what you notice in a different way.
The word is derived from the Greek words para, meaning something faulty, wrong, instead of, and the noun eidōlon, meaning image, form or shape. Pareidolia is a type of apophenia, which is a more generalized term for seeing patterns in random data.