What is the difference between a public key and a wallet address?

The terms "public key" and "wallet address" are both integral parts of cryptocurrency transactions and security, but they serve different purposes in the blockchain ecosystem:

1. **Public Key**:
   - **Definition**: In cryptography, a public key is a cryptographic key that can be freely distributed and is used to encrypt messages or verify digital signatures. In the context of cryptocurrencies:
     - **Encryption**: It is used to encrypt data that can only be decrypted by the corresponding private key.
     - **Digital Signatures**: It is used to verify digital signatures generated by the corresponding private key.
   - **Role**: Every cryptocurrency transaction involves the use of public key cryptography. When you send funds to someone, you use their public key to encrypt the transaction details or verify their digital signature to ensure authenticity.

2. **Wallet Address**:
   - **Definition**: A wallet address, also known as a public address or public key hash, is a string of alphanumeric characters derived from a public key through a hashing process. It serves as an identifier for receiving cryptocurrency transactions.
   - **Role**: A wallet address is what you share with others to receive payments or funds. It is a representation of your public key but is typically shorter and easier to share or remember. When someone sends cryptocurrencies to your wallet address, the transaction is recorded on the blockchain ledger.

**Key Differences**:

- **Purpose**:
  - **Public Key**: Primarily used in cryptography for encryption and digital signatures.
  - **Wallet Address**: Specifically used in cryptocurrency transactions to receive funds.

- **Visibility**:
  - **Public Key**: It can be publicly shared and used for cryptographic operations.
  - **Wallet Address**: It is publicly shared to receive payments but does not directly participate in cryptographic operations (encryption or signature verification).

- **Format**:
  - **Public Key**: Typically longer and in a specific format required for cryptographic operations.
  - **Wallet Address**: Shorter and formatted as a string of alphanumeric characters suitable for sharing.

In summary, while both the public key and wallet address are derived from the same cryptographic key pair (public-private key pair), they serve different functions within the context of cryptocurrencies. The public key is used for cryptographic operations, whereas the wallet address is used to receive payments and identify wallet locations on the blockchain.