State what is meant by the terms: Parallel data transmission Serial data transmission

Mark scheme

Marking points from the official mark scheme (May/June 2015). The mark or mark type is shown in brackets.

1. [(a) parallel] [1 mark] 8 bits/1 byte/multiple bits sent at a time
2. [(a) parallel] [1 mark] using many/multiple/8 wires/lines
3. [(a) serial] [1 mark] one bit sent at a time
4. [(a) serial] [1 mark] over a single wire
5. [(b) parallel] [1 mark] faster rate of data transmission
6. [(b) serial] [1 mark] more accurate/fewer errors over a longer distance
7. [(b) serial] [1 mark] less expensive wiring
8. [(b) serial] [1 mark] less chance of data being skewed/out of synchronisation/order
9. [(c) parallel] [1 mark] sending data from a computer to a printer
10. [(c) parallel] [1 mark] internal data transfer (buses)
11. [(c) serial] [1 mark] connect computer to a modem