What does the term "key length" refer to in encryption?

The term "key length" in encryption specifically refers to the number of bits in the encryption key. A longer key length generally indicates a higher level of security because it increases the number of possible keys, making brute-force attacks more difficult to execute. For example, a 128-bit key has 2^128 possible combinations, while a 256-bit key has 2^256 combinations. This exponential increase in possible keys contributes to the overall strength of the encryption method being used.

Understanding key length is crucial in evaluating the security of encryption algorithms, as it directly impacts how resistant the encryption is to attacks. For instance, modern encryption standards like AES specify key lengths of 128, 192, or 256 bits, with longer keys providing greater security suitable for handling sensitive data. It is important for anyone dealing with encryption to appreciate the significance of key length and its implications for cybersecurity.