How to order input fields? For displaying a content, I can modify the fields order using display and field weights.

However, in a node/add/content-type page the input fields doesn't obey the weight given to the display. How can I reorder the input fields in a node/add/content-type page?
Taking as example the Article content type, on admin/structure/types/manage/article/fields, you alter the field's order in the edit form; on admin/structure/types/manage/article/display, you alter the order the same fields are shown when rendering a node.