One
of the many methods of quantitative analysis available to chemists is volumetric analysis using titration techniques or instrumental methods such
as colorimetry.
You
will use some of them during your IB chemistry course.
The precision of all the methods depend on the chemist's ability to
make up solutions with an accurately known
concentration.
Reading the buret carefully is a waste of time if
you do not know accurately the concentration of the solution
you are titrating with.
Sophisticated machines like
spectrophotometer can only give you precise quantitative results if
calibrated carefully with standard solutions.
A
solution (which you may have prepared) whose concentration you know precisely
and can be used in a volumetric analysis to determine the concentration
of another (by titration for example) is referred to as a standard solution.