|One requires a finer grained access to storage than availabe. Therefore:|
|Read and write blocks of values at the required (desired) grain size. Hold one or more whole blocks in a buffer memory while the finer grained elements are processed.|
|The CDC-6000 reads and writes 60-bit words. Four 12-bit PDP-8 words
are buffered inside the FETCH and STORE
The CDC-6000's paper tape punch driver expects Five 8-bit bytes in each 60-bit word of a binary file.
FORTRAN's formatted I/O reads and writes whole lines consiting typically of 80 to 132 characters.