MSBuild 12.0

MSBuild is now installed as part of Visual Studio rather than as part of the .NET Framework

MSBuild is now installed directly under %ProgramFiles%—for example, in C:\Program Files\MSBuild\.

C:\Program Files\MSBuild\12.0\Bin\msbuild.exe

C:\Windows\Microsoft.NET\Framework\v4.0.30319\msbuild.exe
http://msdn.microsoft.com/en-us/library/dd576348.aspx http://msdn.microsoft.com/en-us/library/dd393573.aspx
A task is the smallest unit of work, in other words, the "atom" of a build. Tasks are independent executable components which may have inputs and outputs.

A target is a named sequence of tasks

Imported files are effectively inserted into the project file wherever they are referenced

four parts of MSBuild: properties, items, tasks, and targets

Clicking the Build command in Visual Studio will execute the default target in the project. Often, this target is also named Build. Choosing the Rebuild or Clean command will attempt to execute a target of the same name in the project. Clicking Publish will execute a target named PublishOnly in the project.
http://msdn.microsoft.com/en-us/library/dd393574.aspx
MSBuild Concepts:
Properties

Items

Targets

Tasks

Comparing Properties and Items

MSBuild Special Characters