As to the meaning/purpose of Shiva; the purpose/meaning of Shiva is Love.
I repeat.
Love.
Why?
There is only Shiva.
Meaning.
All is One and the same.
Don’t get attached to words however.
Replace Shiva with Universal Consciousness or God or Buddha or Allah or the Tao.
Doesn’t change a thing.
Lest return to Shiva.
Shiva is One.
Not two. Shiva is One not wanting to be alone.
It is not good for One to be alone.
Hence One’s purpose.
One’s purpose Companionship.
One’s purpose Friendship.
One’s purpose Love. Hence the Gospel of Love. In conclusion and in most simple terms; the answer to the question “what is the meaning/purpose of Shiva”:
The purpose of Shiva is Love.
Realizing this brings peace to Self/Shiva.
Hence the why of:
Om Shanti, Shanti, Shanti-i.
~ Wald Wassermann, Physicist