It's the first-ever Crypto Voucher, redeemable to BTC! Purchase a voucher. Next, redeem it on cryptovoucher. io and add BTC to your wallet. It's fast, simple and secure! Bitcoin is a digital currency used for fast, secure and low-cost payments without the need for a central issuer or processor. Bitcoins are stored and sent electronically from private wallets. Introduced in 2009, bitcoins have increased greatly in value due to their limited supply and growing popularity.