Share trading systems?

Electronic developments further helped to promote day trading. One important step in facilitating day trading was, therefore, the founding in 1971 of NASDAQ -- a virtual stock exchange on which orders were transmitted electronically. Moving from paper share certificates and written share registers to "dematerialized" shares, computerized trading and registration required not only extensive changes to legislation but also the development of the necessary technology: online and real time systems rather than batch; electronic communications rather than the postal service, telex or the physical shipment of computer tapes; the development of secure cryptographic algorithms etc. All have been materialized.