Zcash (ZEC) is a privacy-focused cryptocurrency launched in 2016 that uses advanced zero-knowledge proofs (zk-SNARKs) to enable fully shielded transactions where sender, receiver, and amount details can remain private. It also supports transparent transactions similar to Bitcoin for flexibility. Operating on a proof-of-work model with optional shielded pools, ZEC prioritizes financial privacy and has been adopted for use cases requiring confidentiality.