One of the many things about my daughter’s Autism is the need to line her toys up as well as color coding things. She has a box of trucks that are all the same except for their coloring. She has to put them in the box color coded or line them up outside of the box, color coded. She’ll also line up each of her animals with their own species, all the dinosaurs line up together, zebras, together, tigers, elephants, etc.
The need for lining things up or color coding is just merely a sense of being in control and or a sense of organization. It also helps relieve anxiety.