When we talk of parallax error, we are talking about one of the most important measurement errors that abounds.
It is also known as error due to parallax and might occur when measurements are taken of objects at positions which are not the correct positions.
In plain physics term, parallax error refers to the shift in apparent position of an object as a result of different viewing position
Hence what we are saying is that the error of parallax is likely to be committed when objects are viewed at incorrect positions causing an apparent shift in their actual position which thus gives rise to an incorrect observation of their real positions
