HowTo: Check If a Directory Exists In a Shell Script

How do I check if a directory exists in a shell script under Linux or Unix like operating systems? How can I check if a directory exists in a shell script on Unix-like system?

To check if a directory exists in a shell script and is a directory use the following syntax:
[ -d "/path/to/dir" ] && echo "Directory /path/to/dir exists."
OR
[ ! -d "/path/to/dir" ] && echo "Directory /path/to/dir DOES NOT exists."

from : https://www.cyberciti.biz/faq/howto-check-if-a-directory-exists-in-a-bash-shellscript/