Describe the difference between symmetric and asymmetric encryption, and specify which type is used for securing transactions on a blockchain.

Symmetric and asymmetric encryption are two fundamental approaches to encrypting data, each with distinct characteristics, advantages, and use cases. Symmetric encryption uses a single key for both encryption and decryption, while asymmetric encryption employs a pair of keys—a public key and a private key—for these processes. In symmetric encryption, the same secret key is used to encrypt and decrypt data. This key must be shared between the sender and receiver securely. Examples of symmetric encryption algorithms include AES (Advanced Encryption Standard) and DES (Data Encryption Standard). The primary advantage of symmetric encryption is its speed and efficiency. It is much faster than asymmetric encryption, which makes it suitable for encrypting large volumes of data. However, the main drawback lies in the need for a secure channel for key exchange. If the shared secret key is compromised, the security of all encrypted communications becomes compromised. For example, in a file-sharing application, if you use the same key to encrypt and decrypt a file, you would need to securely provide that key to the recipient so that they can decrypt it. The secur....