How secure is Hedera?

Could you elaborate on the security aspects of Hedera? I've heard about its distributed ledger technology and the claim of being highly secure, but I'd like to understand the specifics. What kind of encryption does it use? How does it protect against hacks and attacks? Also, what measures does Hedera take to ensure the privacy and confidentiality of its users' transactions? I'm interested in understanding how Hedera stacks up against other cryptocurrencies in terms of security.