Visual Development

"Elan: You know, I had just assumed that your short hair was somehow symbolic of your character growth. Haley: Me too! Guess it was just a crappy haircut."

- The Order of the Stick

You've missed a few episodes of a show you are watching. Shouldn't be a big deal...wait, when did Alice grow her hair out? And why did Bob shave his beard? And did they just kiss!? When did they get together? And why does Charley look so different? And suddenly so much better at sports? Looks like you missed the Wham! Episode and some Character Development.

As vision is our primary sense, using that to show how characters have changed is helpful. In real life, people who go through dramatic changes do sometimes change their appearance. Two people who just had a Relationship Upgrade might change their appearance to better appeal to their significant other. Someone who just lost someone might dress to reflect their grief. The connection may not be made clear, but the visual change coincides with the emotional change.

This trope is very useful in Long Runners, as it allows for the fanbase to differentiate between major arcs by the visual differences. Sub Tropes are Important Haircut, Expository Hairstyle Change and Evil Makes You Ugly (for falls to The Dark Side). Not to be mistaken for Art Evolution.

Anime and Manga

 * Naruto stopped wearing his village headband for a while, after vowing to bring peace to the world. As fate would have it,.
 * In The Melancholy of Haruhi Suzumiya, Kyon notes that she's stopped changing her hairstyle everyday, and takes this as a sign she's interested in someone. Sure enough, she chose Kyon to be her first member of the new student group she formed, known as the "SOS Brigade".

Comic Books

 * In Scott Pilgrim, Ramona Flowers changes her hairstyle and dyes it a new color every three weeks. That is, until her relationship with Scott deepened. Scott suspected that he was the reason she went so long without changing it.

Live-Action TV

 * Farscape: Crichton spent much of season one in his astronaut jumpsuit. In later seasons, after he Took a Level in Badass, he tended to wear the Peacekeeper leathers, which look frickin' awesome. Later, he upgraded to a Badass Longcoat.

Professional Wrestling

 * WWE: When Stephanie McMahon went through a Face Heel Turn, she started wearing heavy makeup and had kinked hair.

Video Games

 * Setsuka from the Soul Series (making her debut in Soul Calibur III) is a woman of European descent who was adopted by a Japanese master and taught to live like any normal Japanese girl from the 16th century. Shunned for being a foreigner, Setsuka dyed her blond hair black to fit in better (this could be discerned only if the player chose Setsuka's 2P costume in III). However, in IV, Setsuka completely ditches the hair dye in both outfits and reverts back to her natural hair color.
 * In Dragon Age II, Merrill's armor changes from black-and-green to white-and-red upon completion of her Romance Sidequest.
 * Commander Shepard's unhealed scars in Mass Effect 2 will become more prominent if s/he follows the Renegade path but heal almost completely if s/he is a Paragon.
 * In the Fable series, your appearance changed according to your morality. If you were good, a little halo would float above your head. If you were evil, you'd grow demon horns.
 * In Star Wars: Knights of the Old Republic series, your character would get either more pale or more healthy looking depending on your Light/Dark side choices.

Web Comics

 * In The Order of the Stick, there was a point when Elan had to think has way out of a problem so that he could save his friends. During this little adventure, he went through a wardrobe change and became Badass. Coincidence? I think not!
 * It was also subverted by Halley, as the quote above shows, took a potion to regrow her hair as soon as she could. But not before they milked her bad haircut for a few jokes.
 * Vaarasuvius, after realizing what a jerk he/she is to others, tied his/her hair back into a ponytail...for some reason.

Western Animation

 * The Simpsons: When Milhouse's parents are thought to be dead, he becomes a Bad Boy loner (including a change of wardrobe) and the girls really go for him.