Systematic or Determinate Errors: Shifts in the measured values from the true values
which reduces the accuracy of a result.
They have a definite source that usually can be identified by the
observer. They can often be eliminated
by simply changing the experimental procedure.
(An example of a systematic error is
misreading a graduated cylinder).
Random or Indeterminate Errors: Shifts in the
measured values from the true values which influences the precision
or scatter of the result. They have an
indeterminate source and are usually not by the observer.
(Examples of random errors might be the
imprecision among multiple readings; or an unnoticed change in temperature,
pressure, or humidity; or a fluctuation in voltage during a measurement).