Before widespread communications networks, credit card imprints were taken with machines that look like [1]. They are still sometimes used when networks are dow

Before widespread communications networks, credit card imprints were taken with machines that look like [1]. They are still sometimes used when networks are down or when there is no phone/Internet network (think temporary locations like fairs and carnivals). The security is that the credit card company will (hopefully) void invalid transactions... [1] http://img.ehowcdn.com/article-new/ehow/images/a04/b9/g6/credit-card-imprinter-work-800x800.jpg http://img.ehowcdn.com/article-new/ehow/images/a04/b9/g6/cre...