Magento Product Categories

We covered many topics like a
(1) Add custom category attribute in magento.
(2) Get all categories in magento.
(3) Get the child category of the category in magento.
(4) Get all categories of the product in magento.
(5) Get the level of the category in magento.
(6) Get the category name, image, description from category id in magento.
(7) Create product category programmatically in magento