In order to build a project, MSBuild must process the project file associated with the project. Every Visual Studio project includes an MSBuild project file, with a file extension that reflects the type of project-for example, a C# project (.csproj), a Visual Basic.NET project (.vbproj), or a database project (.dbproj).

When you create and build solutions in Visual Studio, Visual Studio uses MSBuild to build each project in your solution. It describes the key components you'll come across when you work with project files, and it works through an example of how you can use project files to deploy real-world applications. This topic starts with a conceptual overview of MSBuild and the project file. Microsoft Build Engine (MSBuild) project files lie at the heart of the build and deployment process.