What type of encryption uses the same key for both encrypting and decrypting data?

Symmetric key encryption utilizes a single key for both the encryption and decryption processes. This means that the same key that transforms plaintext into ciphertext is also used to revert it back to its original form. This method is efficient and allows for quick encryption and decryption which can be crucial for performance in many applications.

In symmetric key encryption, both the sender and receiver must have access to the same key and must keep it secret from potential eavesdroppers. The primary benefit is that it generally requires less computational power compared to its asymmetric counterpart, making it faster and suitable for encrypting large volumes of data.

Asymmetric key encryption, in contrast, involves a pair of keys: a public key for encryption and a private key for decryption, thereby differentiating the processes. Hash encryption is a different concept altogether, focusing on transforming data into a fixed-size string of characters (a hash) that cannot be reversed to obtain the original data. Lastly, public key encryption is another term for asymmetric encryption which is characterized by its use of two different keys.