http://www.fmi.uni-passau.de/archive/doc/unix/unixhelp/Unixhelp/shell_bash_hist1.html (Einblicke ins Internet, ~06/1995)By default the previous 500 commands are saved in the command history list.
HISTSIZE=50;export HISTSIZE
This will keep a history of the fifty (50) most recent commands that you have used.