Q:

Do I need to install Visual C++ 2008 Redistributable if my Windows already has Visual Studio 2012 Redistributable?

I am using Windows 10. I am trying to install 1 open source software.
In the readme.txt of that software, it says it requires Visual C++ 2008 Redistributable. I found that my Windows already has Visual Studio 2012 Redistributable installed.
After I install the open source software, it seems that it is working, even though I haven't installed Visual C++ 2008 Redistributable.
Do I need to install Visual C++ 2008 Redistributable if my Windows already has Visual Studio 2012 Redistributable?

A:

You may or may not, depending on the software that requires the redistributable. Some software is written to rely on a specific redistributable, while another software may be written to rely on that older redistributable but is also able to use any of the more recent versions all the way up to the latest version. 
From microsoft's forum:

Visual C++ redistributables do not supersede each other. Some apps may
  be very specific to bind to the exact version of the Visual C++ dlls,
  for example, to make sure the app runs exactly as published. Most
  apps, however, bind to the latest edition of the same major version,
  as it is the default behavior and can benefit from Microsoft's
  security updates. 
There could be multiple versions of Visual C++ redistributables
  required by one app. For example, if an app depending on Visual C++
  2008 redistributable uses a component depending on Visual C++ 2005
  redistributable, the app's developer must ship both versions of Visual
  C++  redistributables.

When in doubt, it's probably a good idea to install the additional one that it says it requires, even though it may not be absolutely necessary. 

