However, not all critiques are created equal, and it can be a daunting task for the novice trying to sort out all the different opinions they might get from varying people. So as a public service, I present the following guide. (Doing the "Attenborough voice" in your head while reading is optional.)
Critiquous Pollyannaish - This well-meaning species is often the least helpful, because no matter how bad the drivel you write is, these people are still going to tell you they think it's a wonderful story. Or idea. Or character. These are the cheerleaders, which it should be pointed out that even really bad teams have. Sometimes they will be right, of course, but all too often they tend to foster the continuing exploits of bad writers. Often because they themselves can't write their way out of a paper bag, and live in dread of someone forcing them to face the truth. Unwilling to do so with their own work, they gladly help others persist in their own states of delusion.
These are probably the people who thought a story about sparkly vampires that had no real plot was a good idea, so as much as it might be desirous to do so, their opinions can't always be discounted.
Critiquous Pretentious - This species is good to consult only if you're interested in writing something Literary. With a capital "L." And possibly italics. Otherwise anything you write will be seen as drivel, catering to the masses, hopelessly commercial, and lacking in any sort of real value. These are the people who keep insisting popular authors are just hacks, no matter how many awards those hacks win. Selling books doesn't count, unless you're on the New York Times Bestseller list, preferably in any category other than popular fiction. Often former English majors.
Critiquous Green-eyed Monstrous - This species can be difficult to spot, as they often masquerade as one of the other species on this list. They can be identified most often not by their actual critiques, but by the snide commentary they are often fond of offering up unasked for and free of charge. Such commentary may include remarks disparaging what you write, how you write, or even that you write at all. Usually stemming from the deep-seated and possibly sub-conscious jealousy that they themselves have no creative talent at all and are stuck in a dead-end career they absolutely hate whereas you are doing something you enjoy. Even if you're stuck in a dead-end career to pay the bills while you do it.
When they do read your work, they may offer damning praise along the lines of "That was much better than I would have expected."
This naturalist is not entirely convinced that c. pretentious is not, in fact, a subspecies of c. green eyed monstrous, if only because the arguments from that species so often center around the tenet that if it sells well and makes the author boatloads of cash, it obviously can't have any literary merit.
Critiquous Familial (also sometimes found alongside critiquous amicus and/or amorous) - Friends, family, lovers, they may all want to read your stories. Tread carefully around this species, as they can exhibit traits from all the other species, and even the most well-meaning members may not be of much help. Especial care should be taken with amicus and amorous that the end critique doesn't end the relationship with unwittingly harsh comments such as, "This was a great parody," when, in fact, it was not meant to be.
Critiquous Honestus - Often the hardest species to find, these are the ones that tell you, in no uncertain terms, the merits and pitfalls of your current work. Recognized most often by their willingness to explain their critiques and have you bounce ideas off of them in order to address the issues they find at fault. Considered the most valuable of the species because once you find one, if they tell you something's good it generally is. Somewhat perversely, they are often the species least likely to be believed by many struggling authors still dealing with nagging self-doubts.
Critiquous Professional - An elusive species, especially for the fledgling writer, and one that can wound even the most seasoned veteran without the proper approach. Often seen as a harbinger that the author has "made it" to a certain level - even if the end critique is somewhat scathing. One positive remark from this species can, if well-timed, make even the most denigrating comment from any of the other species fade into obscurity.
This is not meant to be a comprehensive guide, by any means, as there are numerous sub-species lurking out there in the vast literary wilds, but I hope it has provided some guidance for determining which species you're dealing with in your own habitat.