Microsoft Build Engine (MSBuild), is a platform for building .NET applications. It provides an XML schema for a project file that controls how the build platform processes and builds software. Any question around this in Sitecore context can make use of this tag.
Microsoft Build Engine, better known as MSBuild, is a free and open-source build tool set for managed code as well as native C++ code and was part of .NET Framework. Visual Studio depends on MSBuild, but not the vice versa.