Categories are a group of items with shared characteristics, be it color, shape, size or what it’s used for. The process of categorising (or sorting by type) helps students develop both their literacy and numeracy skills. Knowing how to categorise gives us a foundation to learn, relate, store and recall words.
When a student is learning about categories they are enhancing their vocabulary, which encourages better comprehension and retention of information. And knowing how to categorise is a prerequisite skill for understanding more advanced items with shared character numerical concepts, such as grouping numbers that are odd/even or larger than/smaller than.