It is very hard to define “SUPERSTITION” to a layman
or a kid.
If you define it as belief in something, it is not so.
There are many things all of us believe in that cannot
be proved. At certain times in man’s history, everyone
believed in certain things that we now consider as
Superstitions. And the people who believed in them at
that time were not Superstitious at all!

For example, they believed that the shadow or reflection
of a human being was a part of the soul. So they considered
that you would harm the soul if you broke anything on which
the shadow or reflection appeared. Therefore, they
considered it harmful or “unlucky” to break a mirror.
Today, if someone considers it “unlucky” to break a mirror
he is Superstitious, because today we no longer believe
that a shadow or reflection is part of the soul. So Superstition
is actually a belief or practice that people cling to after new
knowledge or facts have appeared to disprove them.
That is why it is impossible to say when Superstition began.

In ancient times man tried to explain events in the world as
best he could with the knowledge at hand. So he made up
explanations and followed certain practices. The old beliefs
should have died out after being disproved by time.
So the Disproved beliefs became Superstitions.