It's a damn shame. In the United States, at least -- and I imagine elsewhere -- there are only two major camps of denim consumers: one consistent of those who believe that a good pair of jeans is cheap and rugged, and one of those who believe that designer jeans are all about branding and social status, and that pragmatism has nothing to do with denim at all. Of course, both of these camps exemplify patent ignorance.
The word "denim" comes from the name of the place where it was first produced. Serge de Nimes was the name of the cotton twill fabric that the Andre family of Nimes, France invented in the mid-18th century. And the word "jeans" just comes from the French name for the Italian city of Genoa, where light denim fabric first became a fashionable material for use in suits, coats and, particularly, slacks. Now, while the fact is that twill made from fine, well-spun cotton fiber is naturally strong, as just about any other quality cotton textile is, nothing about denim lends it to manual labor; and while dying and washing processes that are used in producing denim are myriad, they are not exclusive to denim, especially in the modern world of chemical technologies -- therefore, there is nothing "high-fashioned" about it. So what is denim good for, you ask? C'mon folks, it's good for making pants.
It was the opinion of one of the greatest designers in the history of men's fashion, Luciano Barbera, that a suit was something to live in. He said that whenever he got a new suit (made for him...), he would eat in it, run in it and sleep in it for three days before hanging it or cleaning it (which was an expensive and new-fangled process in his day). In my opinion, the same goes for jeans. Jeans aren't the contractor's domain, nor the fashionista's. They belong to the Everyman, and they should be treated as such. Unfortunately, as they are not, most people go into buying denim with (sub)cultural bias rather than information. I want to change that -- which is my reason for writing this, the Everyman's Guide to Buying Denim.
Fit
As you might expect, the most important thing to consider when buying a pair of jeans is how they fit. There are a few factors to fit -- waist size, inseam length, rise, crotch depth, pant circumference and hem circumference. I will address each of these individually (for the most part).
Waist Size and Inseam Length:
These are fairly self-explanatory. To determine your waist size, strip to your undies, take a tape-measure, and wrap yourself at the point on your waist from which you want your jeans to hang. Take note of what the tape-measure reads, and, voila, you've got your waist size. While you shouldn't go for a pair of jeans with a waist size less than yours, some people (read: adolescent males) do prefer to buy them two or four inches larger than their actual measurement, for comfort or style. While I would not recommend this to someone who is very physically active in the course of their average day, or anyone over the age of 27, the decision to do this is, obviously, left to your discretion. As for inseam, it is very similar to waist size; as the inseam is the length of each pant leg from the hem to the crotch along the seam that runs from one to the other, taking your measurement for it is simple. Strip to undies, apply tape measure... you know the drill. And, in very much the same way as some people buy up a couple sizes from their waist size, the same is often done with inseam length. Some people prefer jeans that fray on the ground. I'm not "some people", you're probably not "some people", but again, buying up a few sizes in this case is left to your discretion.
Rise:
Rise is a big fashion issue. "Rise" describes where the jeans are supposed to fall on your hips, if you have, indeed, purchased according with your actual waist size. The standard rise -- sometimes referred to as "mid-rise" -- is to just above the bottom of your waist, at about the top of your hips. This rise is relaxed, comfortable, and casual, perfect for the person who wears t-shirts and blouses with their jeans. The "low-rise" is just that, and is most frequently associated with the sexualized fashion that pervades the designer clothing culture. Low-rise jeans are best worn on men with tucked-in button-up shirts (just FYI, jeans should never be worn with dress shirts, only sport shirts) and a belt, and on women who are trying to show off their midriff with a short top. Don't get me wrong, I'm all for low-rise jeans, but be careful with them -- they aren't quite as versatile as their mid-rise friends. As for high-rise jeans... They're sort of out of style. But that doesn't mean that they can't look good, or that you can't get them anymore. High-rise jeans are best on women, with outfits that feature hip-hugging blouses. High-rise jeans usually thin you out above the waist, so the ways in which they should be applied, against, say, mid-rise jeans, are limited.
Crotch Depth:
This one is easy enough. Look guys, there is no commonly taken measurement of crotch depth; I only included it as a section because it is a consideration of both rise and inseam length, making it a slightly more involved one. Really, you just have to try the jeans on that you're thinking of buying before taking them home. Low-rise jeans tend to be high-crotched, mid-rise jeans tend to be mid-crotched, and high-rise jeans tend to be high-crotched; there really is no pattern, especially because those tendencies that I just listed are empirical, and certainly not definitive. Also, keep in mind: a low-crotch gives the impression of shorter legs, a high-crotch longer legs; guys frequently prefer lower crotches, women higher ones. The only thing that's really important here is comfort, but I'm trying to keep it real -- fashion still plays its role here.
Pant Circumference and Hem Circumference:
These are often referred to collectively as "cut" or "style", but I will refrain from using these terms henceforth because their classes ("boot cut", "straight", "narrow", etc.) are inconsistent from brand to brand. Pant circumference is simply how you want the jeans to hug your thighs -- I think it's unnecessary to note that the greater the circumference, the baggier the jeans will be (but I did it anyway). Hem circumference has more to do with the drape of the jeans over your shoes (or whether they stop at, or before, the ankle). There are no regularly taken measurements for either of these dimensions -- they are totally preferential. I think it's appropriate to note that I have, personally, never bought a pair of jeans of my waist size that have been too tight -- and I say this as someone with fairly muscular legs.
Finish
There are three factors of "finish": color, wash and distress. Color is fairly obvious; most jeans are dyed a shade or hue of blue; some are dyed in gray, black, white -- and occasionally, in other colors too. Wash is slightly less obvious. The wash of the jeans refers to how faded the color of the jeans is, and where on the jeans it is faded. Some jeans are faded in the knees, some on the back of the pants; some are faded all over, some aren't faded at all. Your wash preference is totally up to you. And the same goes for distress; distressed jeans are those with stretch lines, holes, or scrapes on the surface. My only advice on this front is not to go too extreme. Big holes, or so many distress lines that your jeans look like a road map -- they're just not cool.
Selvedge Jeans:
"Selvedge" jeans are jeans that are totally unfinished, and that have been hemmed such that they shouldn't fray. They are usually nearly black (these jeans haven't been washed at all, so they aren't faded), and if you fold them, say, at the cuff, and wash them, they will stay that way (hence the name "selvedge" -- that's just a compound of "self-edge"). Selvedge jeans are favorites of jean aficionados, because they are considered the most "authentic" jeans; they fade and distress according to your life habits, rather than to the design of a textile company. Selvedge jeans are usually considered premium, and tend to be very expensive. I'm sure that you'll never buy a "bad" pair of selvedge jeans -- they're known to last forever, thanks to their incredibly tight, sturdy weave -- but you should never feel pressured to own them; they're hard to find, anyhow.
Detailing
There are many tiny details that can distinguish a pair of jeans from the rest; there are also certain minor features that are standard. Most jeans nowadays have five pockets -- three in the front, two in the back -- and decorative riveting. Rivets are usually sand-blasted smoothe, and can be made from any variety of metals or plastics, and in a whole array of colors. Some jeans have zipper pockets (they are difficult to find), and most -- though not by a long shot -- have zip-up flies. Others have button flies, which tend to be more reliable, and easier to repair. Finally, while virtually all jeans have tags or labels on the waistband in the hind, some sport graphic embroidery. I think that this is usually tacky, but it can look good on some people, particularly the younger street folk.
Designer
Guys, I'm going to try to keep this impartial -- which means short and sweet. All I am going to say in this regard is that you should never settle for cheap, generic brand names. Designer jeans get a bad rap for being too expensive, but really, there are only a few super-over-priced jeans on the retail market nowadays -- for instance, True Religion Brand Jeans, Diesel, and Rock and Republic. Running at between $250 and $400 a piece, these jeans lack the quality to justify spending such exorbitant amounts on them. Most worth-while jeans cost between $70 and $200, and are worth every penny. Personally, I own jeans by AG Jeans ($150), 7 For All Mankind($150), Paper Denim and Cloth ($80), Armani Exchange ($115), and Guess by Marciano ($100); other brands worth consideration, among others, are Levis (classics, and relatively inexpensive!), Jordache, Lucky Brand Jeans, Boss Orange Jeans and Mavi Jeans. These brand-name jeans will last decades, fade and distress well, and most importantly, be soft and comfortable from the time you buy them to the day they go too threadbare to wear!
In Conclusion...
Jeans are among the few articles of clothing that well compromise daily versatility with modern fashion. I hope that I have laid out a few dimensions by which you, the Everyman, can contemplate, judge and wear them without skimping in quality. Remember: Jeans are sort of like suits (were in 1800). They should be worn for the sake of wearing them.
References:
http://www.fazeteen.com/fall2002/jeans.htm
http://en.wikipedia.org/wiki/Designer_jeans
If I've left anything out, contact me! I want to help to the best of my abilities with all of your denim decisions!