Plug Boards: Precursors To Software
IBM corporate archivist Paul C. Lasewicz holds a plug board, which is the equivalent of software for the Type 405. Companies would have racks full of plug boards, with each board wired to support a particular type of report--payroll, revenue, stock control, and so forth. Punch cards, seen in the input and output trays of the accounting machine, stored the transactional data, such as employee hours, sales, and orders. Accounting machines had no stored memory, so they were still tabulating devices rather than computers.
RECOMMENDED READING:
Inside Watson, IBM's Jeopardy Computer
What's At Stake In IBM's Jeopardy Challenge?
IBM: From Networked Business To Social Media
IBM Shows Tools For Smarter City Management
IBM Empowers Smarter Cities
Computer History Museum Tour
Great Lost Software: 16 Gone But Not Forgotten