Often you may hear, or even say, stuff like you don't want to be "judged" by others, or how unsuitable, unappealing "judgemental" people are, or that or that sounds judgemental, or how some people are so fast to "pass judgement" on others and don't even take time to know them first. Though the general notion of "judging" is negative, and usually you assume that "passing judgment" on something is a negative thing, I started thinking about the judging itself and whether it was really such a bad thing.
The first thing I realized was that judging is a human trait, a natural way for us to learn and understand our surroundings. No one can really say that they don't judge, for if they don't judge, they don't form an opinion about anything, and someone who doesn't have an opinion about anything is, well, empty. Perhaps from our early days we start judging, by basically coming around something and filing it away in our heads as usefull or useless, or interesting or uninteresting, toy or no-no, and as we grow older we are taught about other ways of filing information from the world in our heads, with labels as "good", "bad", "moral", "immoral", "ethical", "unethical", "honest", "dishonest", "efficient", "wasteful", "easy", "difficult" and so on. We pass judgment when reading the program of a physics class we decide that's going to be hard, or when we think about a spinning class and thing "that's gonna push up my energy levels". In both cases we make a judgement of something we haven't known yet, as you haven't finished yet the physics class, nor the spinning class, but you have a perception of the class and form an idea of it.
Now, unlike in the case of court of law judgments, these judgments we pass obey to no rules and no laws, but those we have formed for ourselves. The same object can be judged over and over, and every judgment to pass can change, like you find out the physics class is really not so hard, but kinda fun - this might be hard to picture, but imagine you are learning about friction, vectors, the movement of bodies and how the colliding of bodies, whether one resting and one moving, or both of them moving affect the motion in both and the energy that's given out - and the spinning class is torture and drains you instead of invigorating you. And you can rejudge and rejudge as often as you like, as often as anything happens to make you change your mind or your perception.
The thing with judgment and judging things as you know them, from the begining on, is that it helps your relate to them, ease the process of knowing them, pre-filing them, if you wish, in your head, so that not everything stands in a jumble in your head, waiting until you've get enough information to formally label it and relate to it. Judging helps you get around the world, and make some order in your head, with all that information that daily pours into you through all your senses. The good thing is that the older you get, the more you experience, the more elements you have to make more and more accurate on your judging.
Imagine your head like a big library, or a computer's hard drive. In the begining the first files or books you get are placed in the nearest shelves or on C:\ , but as more and more books, magazines, pictures or files arrive, you realize you need to start sorting them, arranging them in a way that makes them easier for your to keep them tagged, having those most important or most often used at hand and those that are not, somewhere else, but still easy to find. So you start labeling them, placing them in particular places. In the computer analogy, you create dossiers and sub-dossiers, and put your files in them, and in the library analogy, you create your little lables and tags and put certain books on certain shelves and so on. Experience makes you also kinda like a physician, so when you see a new piece of information coming your way, you look for the tell-tale signs to come up with a diagnosis to catalogue the given object within the most fitting label you have at that moment. You don't make new labels at the begining of the contact with the object (this object is anything outside you, so it can be another person, but it can be also something in you, like an illness or a weird feeling... anything you can form thoughts about). When none of your current labels seem to fit, you always have handy a label known as "weird".
You can imagine "weird" like being "judgment purgatory". It the library analogy, "weird" is the counter or the bin of "to be filed", in the computer analogy is the desktop or the "Received files" dossier. It doesn't mean that things that go under weird are bad, but for instance, if you had a lot of experience pulling things from weird and ending up filing them under bad, immoral, unethical, dishonest, etc, then you tend to consider weird as bad, but technically, even if you have the object filed still on weird, it can go either way, when the weird stops being weird and fits another label or gets a label of its own.
In this sense judging isn't wrong or an impolite thing to do, something that turns you into a moron, but rather something that helps you deal with the world around you.
The thing about "judging" that often comes out as bad is not so much the judging, but rather the condemning some people do. So, there were the judging that goes inside us is much like an eternally open case (seldom or only in very qualifies cases we close the case), some have the tendency to pass an initial judgment, close the case and condemn without giving chance to any further rejudging. Such cases we can see in racism, male chauvinism, manhating, xenophobia, just to mention some. In this case the object has been judged often before coming in contact with the particular object. A male chauvinist do not need to know a particular woman in order to judge her as inferior and a sexual object submited to his service. A manhater do not need to know any particular man to judge him as a pig that's good for nothing but to move furniture and spend money on her.
You judge when you determinate a person is a nice person or a bad person. You condemn when you decide that no one who is gay has the right to marry, or simply when you think that your gay cousin doesn't have the right to marry like you, or the nice girl from the shop, who is lesbian, shouldn't be allowed to wear a wedding dress and marry her sweetheart.
So, don't worry about judging, go and judge, that's fine, just be careful about the condemnings and absolutions you pass.