What does it mean that the memory card is fat?

FAT, also known as document allocation table, is a partially patented document system invented by Microsoft, which is used by MSDOS and all non-nt kernel Microsoft windows.

FAT file system was supported by almost all personal computer operating systems because the computer performance was limited and not complicated at that time. This feature makes it an ideal file system for floppy disks and memory cards, and is also suitable for data exchange in different operating systems. But the disadvantages of fat are as follows:

1, big disk wastes space;

2. Low disk utilization efficiency;

3. File storage is restricted;

4. Long file names are not supported, only 8 characters are supported;