1. white card: a white card refers to a magnetic tape card whose surface color is white. White card is usually the original tape card without any processing, which can be used for some basic storage needs. White cards can be used to record audio, video, data and other information, and can be read and written on appropriate devices.
2. Black card: Black card is a special type of magnetic tape card. It will make its surface appear black through special treatment during the production process. Black cards usually have higher density and quality, and can be used for high-capacity data storage and backup. Black cards are usually used in applications that require greater capacity and reliability, such as data centers and enterprise storage systems.
3. Transparent card: Transparent card is another common type of magnetic tape card. The surface of the transparent card is transparent or translucent, and the data on the card can be understood by observing the tape layer inside the card. Transparent cards are usually used in some applications that need to access and modify data frequently, such as video editing and data acquisition.
It should be noted that the above differences are mainly applicable to the traditional tape storage technology. Modern storage technology has developed many other types of storage media, such as solid-state hard disk (SSD) and flash drive (SD card). These new technologies have improved performance, capacity and reliability compared with traditional tape cards.