Matlab program lines need explanation

Peaks = houghpeaks(H,40,'threshold',ceil(0.3*max(H(:))));

x = theta(Peaks(:,2));
y = rho(Peaks(:,1));
plot(x,y,'s','color','black');

lines = houghlines(BW,theta,rho,Peaks,'FillGap',5,'MinLength',7);
imshow(I); hold on;
max_len = 0;
minlinelen = 15;
for k = 1:length(lines)
   len = norm(lines(k).point1 - lines(k).point2);
   if (len > minlinelen)
    xy = [lines(k).point1; lines(k).point2];
     plot(xy(:,1),xy(:,2),'LineWidth',2,'Color','green');

Can anyone kindly explain me this coding????It may be easy one.,,I guess.. Advanced thanks to all.