However, punchcards were slow and write-once, you can't easily un-punch a hole.

然而，打孔卡速度很慢，而且是一次写入，你不能轻易地取消打孔。

The main program was stored on 62,500 punchcards, roughly equivalent to 5 megabytes of data, that's the size of an average smartphone photo today.

主程序存储在 62,500 张穿孔卡片上，大约相当于 5 兆字节的数据，这是当今智能手机照片的平均大小。