what is the output log in the game data

Assuming you mean the output_log.txt file in the compiled [project]_Data dir. This is where any Debug.* output will go at runtime, as well as output from the Unity engine. For instance:

 Direct3D:
     Version:  Direct3D 9.0c [nvd3dum.dll 8.17.12.6099]
     Renderer: NVIDIA GeForce GTX 295
     Vendor:   NVIDIA
     VRAM:     896 MB
     Caps:     Shader=30 DepthRT=1 NativeDepth=1 NativeShadow=1 DF16=0 DF24=0 INTZ=1 RAWZ=0 NULL=1 RESZ=0 SlowINTZ=0
 desktop: 1600x1200 60Hz; virtual: 3520x1200 at -1920,0
 <I> Initializing (RawInput).
 
 <RI> Input initialized.
 
 Non platform assembly: data-09180048 (this message is harmless)
 Non platform assembly: data-030718D8 (this message is harmless)
 Non platform assembly: data-0307F610 (this message is harmless)
 Non platform assembly: data-091E4F18 (this message is harmless)
 Non platform assembly: data-091F5B00 (this message is harmless)
 Platform assembly: C:\Everything\Files\Unity\build\ReGenesis_Data\Managed\UnityScript.Lang.dll (this message is harmless)
 Platform assembly: C:\Everything\Files\Unity\build\ReGenesis_Data\Managed\Boo.Lang.dll (this message is harmless)
 Your 64 bit Windows installation is missing an imporant service pack patch. Please apply http://support.microsoft.com/kb/976038 to ensure stability.
  
 (Filename: C:/BuildAgent/work/6bc5f79e0a4296d6/PlatformDependent/Win/wow64.cpp Line: 42)
 
 ratio is 1.333333
 UnityEngine.Debug:Internal_Log(Int32, String, Object)
 UnityEngine.Debug:Log(Object)
 UnityEngine.MonoBehaviour:print(Object)
 MenuButton:Awake()