Creating a Configurable Product in Magento
Magento has a wide variety of product types, ranging from Simple products (where you have one product with no selectable options), to Configurable products (with multiple selectable attributes), Group products (Displaying multiple products on one page), and bundled products (a selection of a number of different products, purchased together)
The below text runs the details of how to set up a configurable product.
Configurable Products let users select from a number of selectable options. For example, you may wish to sell an T-Shirt in a range of colours and sizes. To do this you would need to create the six variants as individual products (with their own SKU’s) add the six variations to a single configurable product which will be used for display, where users can then select the size and colour, then add to cart.