In Section 8: Network Security, you learned about port scanning, specifically using the Nmap tool. As you may recall, port scanning tools display which ports on a network are open for communication. Whether or not a port is open can help with determining the next steps a pen tester might want to take in launching attacks against a network. Creating a simple port scanning tool in Python is easy, and is a great way to both learn socket programming with Python, and learn how port scanners work.