What is Visual C++ 2005 Service Pack 1 Redistributable Package for?

I am using Poco library and when running my program on other machines which don't have VS2005 installed, I have to install "Microsoft Visual C++ 2005 Service Pack 1 Redistributable Package ATL Security Update", otherwise the the program will give error when launching.

What is this redistributable package for? Is there any way to avoid开发者_StackOverflow installing this but still let my program running well?

Also, there're so many vcredist_x86.exe out there. How can I know which one is necessary or not when getting error? Thanks.

This package contains the msvc*.dll files that your program depends on.

These files contain functions that (almost) every app compiled with VC++ uses for internal memory management, etc.

If you don't want this dependency, then you need to statically link to the runtime library. (Which according to Microsoft is not recommended.)