Gorden Allport (1961) defined personality as "Personality is the dynamic organization within the individual of those psychophysical systems that determine his characteristic behavior and thought".
Personality tests also help the individual to understand and choose their career. Certain personality types go well with certain jobs. Thus taking a personality test will help the individual understand what career they should choose.
Online personality tests are trending now as it is easily accessible for individuals and anyone who is a bit technology savvy.
These personality tests can be taken by anyone be it kids, students, adults. http://www.brainwonders.in/psychometric/personality-test.php