"Ordered" means "having order", not "having order that I wanted it to have". The order, unless you have sorted it, is the order of creation of elements. Which may not be what you want if you want numeric key order and you insert keys in different order. So what it means is that PHP array/hash structure supports the concept of order - so you can ask questions like "what is the first element? what is the next one?" Not for all hash structures this is true - for many hashes, asking "what is the next element after this one" is meaningless since there's no order defined on elements.
I got it now. The issue is the language barrier. And by language I mean my native language where "ordered" is sometimes used as synonym for "sorted" (at least in CS and Math fields), hence the confusion.