Can somebody tell me what actually does this in java 2d arrays :

for (int i=0; i<RUNNERS; i++) {

for (int j=i+1; j<RUNNERS; j++) {

if (racer[j][0]<racer[i][0]) {

// swap times and positions

int temp = racer[j][0];

int temp2 = racer[j][1];

racer[j][0] = racer[i][0];

racer[j][1] = racer[i][1];

racer[i][0] = temp;

racer[i][1] = temp2;

thanks.