They do the categorization thing really well, there's "catalog pages" that reference item categories, and item categories can be attached to multiple different catalog pages, and items are categorized by tons of different metrics (length, diameter, thread pitch, head shape, material, color...).
And while that's a pretty generic statement - there's lots of stores that let you filter by material or color, after all - it's all executed SUPER well. I often use it just to get a broad idea of what hardware actually exists/what the terminology I need to search for elsewhere.
I knew someone who worked on their system and apparently it's all COBOL on the backend too lol. I'm sure there's some modern tech on the frontend but I bet all the inventory stuff/etc and the warehouse terminals are running on COBOL.