Why we do division in those steps told, and who invented division? i know how to divide but i dont quit understand why we use those steps told in schools.
like for example 
  ____
3/450    150  quotient
  3
 -----
  15 
  15
------
  000

could someone please tell me why we do these steps is there any other method or can someone explain why?

Taking your example, write 
$$
  \frac{450}{3}
= \frac{4 \times 100 + 5 \times 10 + 0 \times 1}{3}
= \frac{4}{3} \times 100 + \frac{5}{3} \times 10 + \frac{0}{3} \times 1.
$$
We will arrange the terms so that the standard method is suggested.
First compute $\frac{4}{3} \times 100 = \left(1 + \frac{1}{3} \right) \times 100$ first; next, take the piece $\frac{1}{3} \times 100$ and add it to the piece $\frac{5}{3} \times 10$ to get $\left(\frac{10}{3} + \frac{5}{3}\right)\times 10 = \frac{15}{3} \times 10 = 5 \times 10$. The last piece is just zero. Your conclusion is
$$
  \frac{450}{3}
= 1 \times 100 + 5 \times 10 + 0 \times 1
= 150.
$$
I hope this helps!
