Public Address
A public address is the shareable string, derived from your public key, that others use to send you crypto.
In depth
It is like an account number you can post anywhere safely. Addresses differ by network — a Bitcoin address starting with "bc1" will not work on Ethereum — and sending to the wrong network usually means permanent loss. Many wallets generate a fresh address for each receipt to improve privacy.
Why it matters
Every deposit starts with copying an address correctly; a single wrong character can be irreversible.