Penetration testing (pen testing) is a type of security assessment where a team of security professionals, known as the "white team," attempts to identify vulnerabilities in an organisation's security infrastructure by attempting to exploit them. The goal of pen testing is to identify vulnerabilities that could be exploited by attackers and provide recommendations on how to fix them.
Red Teaming, on the other hand, is a more comprehensive approach that involves simulating a real-world attack on an organisation's security infrastructure. The Red Team uses tactics similar to those used by actual attackers and attempts to breach the organisation's defences. The goal of Red Teaming is to identify weaknesses in the organisation's security posture and provide recommendations on how to improve it.
In summary, pen testing focuses on identifying vulnerabilities, while Red Teaming focuses on identifying weaknesses in the organisation's security posture and providing recommendations on how to improve it.