Here document
Output with Expansion
cat << EOF
Text to write goes here
Variables are expanded: $PATH
EOF
Output without Expansion
cat << "EOF"
Text to write goes here
Variables are not expanded: $PATH
EOF
Ignore Tab Indentation
cat <<- EOF
Text to write goes here
Tabs are ignored, so you can indent the source code without affecting the output.
If you do want to indent the output, do it with spaces
EOF