LINQ defines standard query operators that allow code written in LINQ-enabled languages to filter, enumerate, and create projections of several types of collections using the same syntax. Such collections may include arrays, enumerable classes, XML, datasets from relational databases, and third party data sources. The LINQ project uses features of version 2.0 of the .NET Framework, new LINQ-related assemblies, and extensions to the C# and Visual Basic .NET languages. Microsoft has distributed a preview release of LINQ, consisting of those libraries and compilers for C# 3.0 and Visual Basic 9. Other languages, such as F# and Nemerle, have also announced preliminary support.

The .NET Framework class library is a library of classes, interfaces, and value types that are included in the Windows Software Development Kit (SDK). This library provides access to system functionality and is designed to be the foundation on which .NET Framework applications, components, and controls are built.

refer http://msdn.microsoft.com/en-us/library/ms229335.aspx

Different parameter data types, different number of parameters, different order of parameters.

XML documents. It differs from HTML, the markup language most often used to present information on the Internet. HTML has fixed tags that deal mainly with style or presentation. An XML document must undergo a transformation into a language with style tags under the control of a style sheet before it can be presented by a browser or other presentation mechanism. Two types of style sheets used with XML are CSS and XSL. Typically, XML is transformed into HTML for presentation. Although tags can be defined as needed in the generation of an XML document, a document type definition (DTD) can be used to define the elements allowed in a particular type of document. A document can be compared by using the rules in the DTD to determine its validity and to locate particular elements in the document. A Web services application's J2EE deployment descriptors are expressed in XML with schemas defining allowed elements. Programs for processing XML documents use SAX or DOM APIs.

The test object model is a large set of object types or classes that QTP uses to represent the objects in our application. Each test object has a list of properties that can uniquely identify objects of that class