export

SYNTAX
      export [-fn] [-p] [name[=value]]

OPTIONS
      -f   The names refer to shell functions; 
           otherwise the names refer to shell variables
      -n   No longer mark each name for export.
      -p   Display output in a form that may be reused as input. 

If no names are supplied, or if the `-p' option is given, a list of exported names is displayed.

The return status is zero unless an invalid option is supplied, one of the names is not a valid shell variable name, or `-f' is supplied with a name that is not a shell function.

export is a BOURNE shell command and a POSIX `special' builtin.

Example - local variables

old_file=export.csv
new_file=last.csv
mv $old_file $new_file

Example - global variables

mydepartment=Sales ; export mydepartment
mycustomer='Brown Brothers' ; export mycustomer

"An average user will saturate their cognitive capacity if they have more than seven things to remember"

Related Linux Bash commands:

env - Display, set, or remove environment variables
echo - Display message on screen
hostname - Print or set system name
local - Create variables
printenv - Print environment variables
readonly - Mark variables/functions as readonly
shift - Shift positional parameters
unset - Remove variable or function names

Equivalent Windows XP commands:

SET - Display, set, or remove Windows NT environment variables
SETX - Set environment variables permanently