export

export marks an environment variable to be exported with any child process. Any child process will will inherit the variable along with any other marked variables

$ NAME=alice
$ echo $NAME
alice
$ cat test.sh
#!/usr/bin/env/bash
echo $NAME
$ ./test.sh

$ export NAME
$ ./test.sh
alice
$ export NAME=bob
$ ./test.sh
bob

Useful Options / Examples

export -p

$ export -p
declare -x SHELL="/bin/bash"
declare -x USER="username"
declare -x VAR="value"
...

Break it down

Will list all variables that are currently marked to be exported