The main difference between Windows3.1 and Windows95 is that the latter provides 32-bit (4GB) linear address space. This address space is divided into three parts; Private address space (0 to 2GB), Shared address space (2GB to 3GB), and System address space (3GB to 4GB). The names show how they are used. Calls to system DLL (Dynamic Link Library) make the libraries mapped them onto the System address space, and they can be shared among processes. Like we have seen in the unit of segment length ( limit) above, compatibility with 16-bit application has still importance in Windows95. Windows95 privies a routine called thunk which takes care of translations between 16-bit 32-bit addresses.