libwnck is Window Navigator Construction Kit, i.e. a library to use for writing
pagers and taskslists and stuff.

libwnck is not supported in the devel platform, which means OS vendors won't
guarantee the API/ABI long-term, but authors of open source apps should feel
free to use libwnck as users can always recompile against a new version. The
API/ABI has historically changed very little: libwnck authors are not changing
it gratuitously or without soname increments.