An obsolete machine formerly used to punch a pattern of holes in a punched card. The pattern had a coded relationship to the data passed to the machine from another data-processing machine or an operator at a keyboard.
科学参考收录了60776条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。