prelink is a free program written by Jakub Jelínek of Red Hat for POSIX-compliant operating systems, principally Linux (because it modifies ELF executables). It is intended to speed up a system by reducing the time a program needs to begin. Actual results have been mixed, but it seems to aid systems with a large number of libraries, such as KDE.
The equivalent process on Mac OS X is called "prebinding".
Read more about Prelink: Method, Randomization, Possible Issues, See Also