On TON an address has the form workchain:hash (e.g. 0:abc...). In user-friendly form it's encoded as base64url with prefixes EQ (bounceable) or UQ (non-bounceable).
Bounceable (EQ) — if the transaction fails, the funds bounce back to the sender. Used for contracts. Non-bounceable (UQ) — if the transaction fails, the coins burn. Used for wallet addresses.