We begin our Journey in to CCK 1.x Wonderland by defining a field. Developing a CCK Field requires working with three systems of hooks: Fields(Data Model), Widgets(User Interfaces/Field Input), and Formatters(Ouput).
We're going to start with Field hooks, since they let CCK know we offer a field.
This hook lists the fieldtypes implemented in our module. It returns an associative array of machine readable names and human readable labels for each of the field types implemented in the module.
* Implementation of hook_field_info().