What are the differences between stateful and stateless firewalls?

Stateful firewalls maintain context about active connections and can make decisions based on the state of the connection, such as whether it is part of an established session. This allows them to track the state of active connections and only allow traffic that is part of a legitimate session, enhancing security by effectively filtering out unauthorized or potentially harmful traffic. On the other hand, stateless firewalls filter packets based solely on individual packet information without considering the context of the overall connection. Stateful firewalls provide better protection against sophisticated threats and help prevent attacks like session hijacking or IP spoofing, making them more effective in enhancing network security compared to stateless firewalls.