Hi, in the introductory example I see this: int a = cb[0]; // a == 1 int b = cb[1]; // b == 2 int c = cb[2]; // c == 3 // The buffer is full now, pushing subsequent // elements will overwrite the front-most elements. cb.push_back(4); // Overwrite 1 with 4. cb.push_back(5); // Overwrite 2 with 5. // The buffer now contains 3, 4 and 5. a = cb[0]; // a == 3 b = cb[1]; // b == 4 c = cb[2]; // c == 5 and I would ask why the 4 and 5 are in the 2nd and 3th position instead of 1st and 2nd respectively. I thought that it worked in the following way: 1 2 3 1 2 3 1 2 3 [A][B][C] -> push_back(D) -> [D][B][C] -> push_back(E) -> [D][E][C] I need a circular buffer for buffering network data and I need that the old data is replaced but doesn't change its position.. Thanks, Daniele.