Downloadable computer software platform for facilitating and administering payment, banking, credit card transactions, debit card transactions, payment card transactions, automatic teller machine transactions, stored value transactions, electronic funds transfer, electronic payments, electronic processing and transmission of bill payment data, cash disbursement, transaction authentication, financial transaction routing, monetary authorization and settlement services, fraud detection and control, disaster recovery and encryption services; downloadable computer software comprising a digital wallet that stores customer account information to access coupons, vouchers, voucher codes and rebates at retailers and to obtain loyalty or monetary rewards that can be credited to their accounts; downloadable computer software for facilitating payment transactions by electronic means over wireless networks, global computer networks and/or mobile telecommunications devices; computer hardware and downloadable encryption software, downloadable encryption key software, downloadable software for accessing and creating digital certificates, downloadable software for accessing and creating digital signatures, downloadable software for secure data storage and retrieval and transmission of confidential customer information used by individuals, banking and financial institutions; downloadable computer software for automating a process for authentication of identity using existing databases in connection with the issuance and management of digital certificates used for authentication or encryption of digital communications, or authentication of a digital signature in an electronic transaction or communication, over the Internet and other computer networks; downloadable software application for use in connection with contactless payment terminals for the purpose of allowing merchants to accept contactless mobile commerce transactions, contactless presentation of loyalty credentials, and contactless redemption of coupons, rebates, discounts, vouchers and special offers; downloadable computer software for encrypting and protecting the integrity of data and electronic communications over computer networks; downloadable computer software for implementing encryption, authentication, access control and other security features within computer networks and through external connections; downloadable computer software for implementing security methodology involving encryption of payment card numbers and related data and transmission over computer networks