Many years ago, roughly around the time Ace of Base hit their peak, I took a brief hiatus (lit. "period of time") from baseball. When I finally returned to the sport, I noticed that the uniforms had changed. I don't just mean team logos or uniform fonts, I mean that baseball players went from wearing tight, calf-length pants with stirrup-socks to looking like they've congregated on a baseball diamond for some sort of elaborate sleepover, which for some reason involves a lot of spitting.
It's not the first time that the look of uniforms have changed, however. If you were to go all the way back to the time of Ancient Greece, you'd notice two things: first, you must have somehow come into possession of a working time machine, and second, the athletes didn't wear any clothes. The motto of those early Olympians was, "You Have to Really Want to Watch Us Play," and they competed in the games wearing nothing but a protective layer of olive oil, in case they ever were confronted by the menace of naturally-occurring breadsticks. It certainly made the Javelin Toss a lot more interesting, if you catch my drift.
The first baseball uniforms, judging by the official photographs, were made of heavy materials like wool, flannel, and surplus mustache. Baseball teams back then had to keep at least 50 men on a roster, because players would routinely die of heat stroke while performing physically taxing feats, such as scratching their groinular regions. This was the origin of the "neighborhood play," which dictated that a runner was considered "out" if the shortstop passed out within three feet of the base while attempting to transfer the ball.
Near the end of the 19th century, teams began experimenting with having each player wear a different colored uniform based on his position, which in theory would make it easier for scorekeepers to continue incorrectly assigning errors to the right players. Unfortunately, because there was a serious lack of women involved in the sport, no one knew that you were supposed to sort the pre-washed laundry according to color similarity, so eventually all of the uniforms came to resemble swamp muck. The result was the St. Louis Browns.
As the 20th century unfolded like a poorly thought out simile, baseball teams introduced the practice of having two different kinds of uniforms, one for use at home games, and a slightly altered version for use on the road. This served both aesthetic and functional purposes. It would now be easier to distinguish which of the two teams was the visiting team (usually the one standing in a group 20 miles from the stadium, confusedly hovering over a map), and more importantly, it was more hygienic, because after a 10-day home stand, the average player's uniform would be giving off aromas powerful enough to damage entire wheat harvests within a 50-mile radius.
Other changes soon followed. The New York Yankees popularized the use of pinstripes, because, as legend has it, they wanted to make Babe Ruth look less obese. This strategy ultimately failed because the pinstripes did nothing to hide the fact that he was eating substantial herds of livestock on a daily basis, but the team liked the look of the uniforms, so they stayed.
In the late 1920s, the Cleveland Indians, along with the Yankees, started wearing uniforms with numbers on the backs of the shirts. As televised baseball became more and more prevalent, teams also began putting players' names on the jersey backs. This allowed fans at home to identify, with perfect accuracy, which players to complain about the next morning at work. It also enabled fans at the stadiums to interact on a more personal level with the players, a benefit which persists even today. Instead of having to yell, "Hey, 25, you SUCK!", you can now yell with complete confidence, "Hey, Tex ... eee ... ay-ahhh ... Tex-ee-ay-ee-ahhh ... Tex-err-eeyahh ... hey, 25, you SUCK!"
The drawback of having names on the backs of uniforms is that, once in a while, you end up with a player whose last name is roughly 28,000 letters long (e.g., Jarrod Saltamacchialattamatalchisaltia), which means that either his name takes up the majority of his uniform and sometimes spills over onto the field, or the letters must be reduced to a height of approximately three pixels (or 4.5 Pedroias). Eventually, as technology advances, teams will do away with player names and numbers completely, and just emblazon a QR code on the jerseys so we can scan them with our phones, go right to a player profile app, and press the "You SUCK" button.
As for pant lengths, there was at one time a completely legitimate reason for keeping them at knee-length, in that it helped the umpires more readily identify the lower limits of a player's strike zone. However, as the Major League Umpires Association has grown in strength and influence, it is no longer necessary to help them delineate the strike zone. The general feeling among umpires today seems to be, "I have a strike zone, but it was designed by a heavily intoxicated Salvador Dali, and I may have left it in the trunk of my car, so good luck finding it today."
And that brings us up to the present day, in which very few players still wear the old-style short pants and high socks, and most players wear their pants so long that, quite frequently, a team's first baseman and left fielder will be seen wearing the exact same pair of pants.
I would blame the whole thing on Bud Selig and issue him a heart-felt "you SUCK!", but I can't seem to locate his QR code.