Bash keeps a list of two types of variables: ICE-unix/22106 SHELL=/bin/bash SHELL_LOGIN=--login SHLVL=2 SSH_AGENT_PID=22161 XKEYSYMDB=/usr/X11R6/lib/X11/XKeysymDB XMODIFIERS=@im=none XTERMID= Then a new subshell is started, in which the variable exported from the parent is visible..