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Systems need a way to store information in persistent storage, such as SPI flash, and an SD card, EEPROM, etc.
Persistent information stored could be:
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Arbitrary data must be able to be written and read persistently. Files will only be written to and read from sequentially, random access is NOT required.
Files can be "read only" once closed, the system does NOT need to support writing to old files, but old files must be able to be read from.
The system must be able to store multiple files.
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Writes to blocks of a storage device should be kept to a minimum. Many devices have a limited numbers of writes so the filesystem needs to be conscious of this an and efficiently write blocks. For example, don't read a block, change a single byte, and write it back for every byte written to the filesystem, instead buffer data until you have a full block.
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