Is Periodic Convolution Same as Circular Convolution? I know exactly what is periodic convolution. But i don't know if circular convolution means to be the same thing!
You did not give specific details on how you define periodic or circular. Assuming standard definitions, the answer is yes.

Standard infinite-support data is treated with standard convolution. When the support  is finite, the "outer unknown samples" require assumptions. 

Zero-valued outside samples is a common assertion. Another option, often used with Fourier or wavelet transforms, consists in arranging finite-support data on a ring or torus, the first sample following the last one. 

It is often termed periodic, cyclic or circular, with a similar meaning.