Sourcing variables from other files using Source command (Bash)
When a child process is started from a BASH script any evironment variables are lost created or changed in the child are lost. If the process or script is called using the source command (abbreviated to a full-stop) a child process is created and variable changes or additions are not lost.
bg1.sh:
place=Monaco
bg2.sh:
bg1.sh
echo "Place is: $place"
# Outputs "Place is: " as the variable was set in a different (child) process
. bg1.sh
echo "Place is: $place"
# Outputs "Place is: Monaco" as the variable was set in the same process.