UPDATE: Earlier this blog post was big and have my inputs too but majorly the intent was from visual studio hacks link. Now I've removed that and suggest you to go directly to this link http://visualstudiohacks.com/articles/visual-studio-net-platform-target-explained/. They have explained it very nicely.
Team Build deals with solution configurations - these are the platforms (e.g. .NET or Win32) and configurations (e.g. Debug or Release) you typically see in combo boxes within Visual Studio when you have a solution loaded (if you hover over these boxes the tooltips will say "Solution Platforms" and "Solution Configurations", respectively).