The PL4E Package

There are lots of products around, and each has its own set of attributes. Books have authors and bindings, clothes have colors and sizes, etc.
PL4E takes all that into account by defining classes and attributes. Size, Color, height, address, phone number, are all attributes of an object. PL4E enables you to manage attributes for products as well as for users.
Classes define groups of attributes: The set of attributes for books (Author, Binding, etc.) is a class and the set of attributes for clothes (Colors, Sizes, etc.) is a class, etc.
The set of items having the same attributes are said to belong to the same class.