1.What does WSDL stand for?
Web Services Description Language.  It is a XML document that contain the serialized version of all methods and classes published by the web service.

2.What does UDDI stand for?
Universal description, discovery and integration. It is a standard that provides a universal way of describing a web service.

3.What are the transport protocol you use to call a Web service?
HTTP, SOAP (Simple Object Access Protocol) is the preferred protocol.

4.In .NET can you use collection types such as ArrayList as parameter type for your web methods?
No you can’t, because the container type will not be properly describe by the WSDL to the client application. It is recommended to use Array of objects, so the object type will be clearly describe to any client application independently of the platform.

5.Why web service is commonly called loosely couple solution? What is a tightly couple solution?
Web service is consider a loosely couple solution because it can be use across different applications and different platform the client application do not need to have any knowledge at all of the Webservice internal implementation.
Per comparison to Web service, Remoting is consider a tightly couple solution because it can not be deployed across platforms and the client application must have an intimate knowledge of the server application.