How to declare a memory block of required dimensions in C?

I want to declare a memory block of size 256 bytes each of 16x16 bytes.
Using malloc(256) we can declare 256 bytes.But I want it as 16x16 bytes.Any one help me??

You can create an array of 16 elements and within a for loop

Use arr[i] = malloc(16);

You are talking about a 2 dimension array, each element of 16 size and has 16 such elements?