The other systems mentioned above, started out by translating CHS(cylinder head sector) utilized by hard disk operating systems and translating that process, to LBA(logical block address) environments. Flash type devices are LBA environments, where PC OS's can not run them direct, an abstract layer sits between the environments. This environment also utilize's an overhead of hardware(RAM) needed for processes involved for the shadowing or paging of data.

rephrase..

The other systems mentioned above, started out by translating CHS(cylinder head sector) utilized by hard disk operating systems and translating that process, to LBA(logical block address) environments. Flash type devices are LBA environments, where PC OS's can not run them direct, an abstract layer sits between the environments. These abstracts also utilize's an overhead of hardware(RAM) needed for processes involved for the shadowing or paging of data.

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