Configurable Products in magento

A Configurable Product is one where the customer gets to choose an atribute of the Product. For example, a pair of shoes is a Configurable Product if the customer gets to choose the size. Likewise, a shirt is also a Configurable Product if the customer can choose the size and colour. In our demo store, we will create a Configurable Product by enabling customers to choose the grind for a coffee.

A Configurable Product is actually a collecNon of Simple Products. Think about a shoe example. In the inventory, the store has many different sizes of the same model of shoe.
Each size is in a different shoebox, and has a different SKU. Each size is, essenNally, a different Product. When a shopper selects a specific size, (s)he is really selecNng a specific Product
with its own, unique SKU.

This means that for every choice you give your customers for a Configurable Product, you need to create a Simple Product. For example, suppose you sell a shirt in the following configuraNons:

Size Color SKU
small blue shsmbl
medium blue shmebl
small red shsmre
medium red shmere
large red shlare

In this case, you would allow the customer to choose two Atributes for this Configurable Product: size and color. Hence, you would create five Simple Products.