Serial Advanced Technology Attachment was developed because of the physical limitations of PATA that is evident within all types of parallel transmission. Parallel transmission works best when the distance is short and certain speeds are not exceeded. One problem with parallel transmission is known as skew and this means that the signals on the parallel wires are received at the source at different times. Serial transmission overcomes these short comings and is the type of transmission used for all long distance data transmission.
SATA cables are much more compact that PATA and this allows a better internal airflow and a greater bandwidth because the parallel problem of 'cross-linking' is avoided.
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