Most workers are paid by the amount of TIME that they work.
For example:
Some people are paid according to the amount they produce or sell; this can usually only apply to factory workers or salesmen. This is known as PIECE RATES.
Obviously it is difficult to measure the ‘output’ of some jobs; people working in health and education, or in offices, are obvious examples. They have to be paid by the amount of time that they work. Piece rates could also mean that people get less money through no fault of their own – the machine breaking down for example. On the other hand piece rates do reward those who work hardest and are more successful and also reduce the need for supervision; if you are ‘slacking’ and not producing the goods, you will simply not get the money.