* Binding : Defines as well as determines the protocol as well as the data format for each port type
* Message : Defines the data elements for each individual operation. It could be the entire document or an argument yet to be mapped
* Operations : Defines the operations to be performed for processing a message
* Port Type : Defines the collection of operations which can be performed for binding
* Types : Defines the message data types, in the form of XML schema, used by the web services
