Essential tremor can be seen at resting or during any movements, but intention tremor, also known as cerebellar tremor, can be observed when the extremity approaches a certain object. For example, in finger to nose test, the amplitude of intention tremor increases as the finger approaches the nose.

@shunsuke koga

Thank you sir for responding.

so intention tremor will not be at rest.

@abdelrahman Ibrahim Abushouk :

Thank you for the answer .

here the difference lies only in age, the rest is still confusing and they seems same to me, like both are absent at rest and exagerrates with movement !

You are right, it is the tremor observed also at rest or when voluntary movements are executed. There is no fixed association whith age.