Relationship between Ethereum Address and public key

Question

Understand ethereum Address is a hash of a public key. We still need to encrypt message with public key to be verified with private key.

What is the use of the Ethereum address in the first place?

Answer 1

At the first place it is used to specify it destination/receiving end.

This may clear more:

An Ethereum address represents an account. For external owned accounts, the address is derived as the last 20 bytes of the public key controlling the account, e.g., cd2a3d9f938e13cd947ec0i8um67fe734df8d8861. This is a hexadecimal format (base 16 notation), which is often indicated explicitly by prepending 0x to the address. Since each byte of the address is represented by 2 hex characters, a prefixed address is 42 characters long.

Answer 2

we use addresses in general for 2 reasons :

• 1- addresses are shorter than public keys. a public key is 64 bytes(128 hex characters), whereas an address is 20 bytes only(40 characters ).
• 2- addresses are hashes of the public key, therefore they provide more security even against quantum attacks.

Answer 3

We don't need to "encrypt" anything in ethereum. Public/Private keys are used for digital signatures. Transactions are signed with private key and verified with public key.