Cryptocurrency wallets store the public and/or private keys for cryptocurrency transactions. They can exist in various forms including hardware wallets, software wallets (mobile or desktop), web wallets, and even paper wallets. Each type of wallet offers different levels of security, convenience, and utility. Wallets do not actually store the cryptocurrencies themselves but rather allow users to access their funds on the blockchain. For example, when you send Bitcoin to someone, your wallet signs the transaction with your private key and broadcasts it to the network.