Forward Secrecy (sometimes known as 'Perfect Forward Secrecy' or PFS) is a cryptographic technique that protects previous communications sessions even if a server’s master keys are later compromised. Despite being simple to enable for HTTPS connections, many servers are not configured this way, and we recommend enabling forward secrecy to improve security. Note that we don't generally like the word 'perfect' when used to describe cryptographic protocols -- even the best protocol can be broken by a flaw in implementation, random number generator, or by advances in cryptanalytic techniques. Even so, it is important to enable the best security available, while keeping informed of new attacks and protocol improvements.