Question from the Algorithmics - Fundamentals test

We use with the following code a method of sorting by fusion in order to sort a large number of data. What do the parameters A, i and j correspond to?

    function merge_sort(A, i, j) 
    {
            If i<j 
    {
            k = (i+j)/2;
            merge_sort(A,i,k);
            merge_sort(A,k+1,j);
            merge(A,i,k,j);
        }
}