We have all seen the original site and we have all recommended it but, as with everything else about parrots, we have learned more in the last years and the notion that all species poop the same has become obsolete. The link below is better but still a bit incomplete, I think, because it doesn't have pictures of normal poop for different species and people become confused by written explanations.
The thing to take into first consideration when analyzing poop is the species. Species that, as stated in the article, eat 'wet' things will have a much more 'liquidy' poop than species that tend to eat dried or harder things. So, although macaws, cockatoos, grays, budgies, tiels, etc should have all three elements of poop separate with 'tubes' nicely formed, species like lories will have almost liquid poop and species that are mainly fruit eaters will have a much softer, wetter poop with not so formed 'tubes'. The reason why I am now posting this is that the previous owner of my new caique, Condorito, was feeding it only dried fruits and not fresh was because, when she did, the poop would not look 'normal' to her BUT IT WAS! Same thing with all the psittaculas and most of the conures - please do not look for perfectly formed poop all the time because a bird that eats lots of fruit and gloop, chop, mash or whatever other staple you are feeding will not have it - but this is the norm for them.
http://www.mickaboo.org/sites/default/f ... pology.pdf