(system-type)returns a symbol indicating the type of the operating system for a running MzScheme. The possible values are:
(system-library-subpath) returns a relative directory pathname string. This string can be used to build pathnames to system-specific files. For example, when MzScheme is running under Solaris on a Sparc architecture, the subpath is "sparc-solaris", while the subpath for Windows on an Intel architecture is "win32\\i386".
(version) returns an immutable string indicating the currently executing version of MzScheme.
(banner) returns an immutable string for MzScheme's start-up banner text (or the banner text for an embedding program, such as MrEd). The banner string ends with a newline.