The new version nbody1.tar.Z is full REAL*8 (corrected 10/2007).
The file nbody1_real4.tar.Z is the old version with mixed
REAL*4/*8 precision which is kept for historical reasons.
nbody1h.tar.gz is a Hermite block-step code for workstations
and GRAPE developed at IoA in 1991 with Jun Makino. It is
based on the classical nbody1 code.