Mario Cap

Mario's Cap is an important part of Mario's clothing. The hat is red and has Mario's "M" symbol. This hat has appeared in every game featuring Mario (with the exception of Dr. Mario games). Mario has worn the same hat since he was a baby.

Importance
Mario was given his hat in his first appearance (Donkey Kong) because of the limited advances in video game graphics when the game was made. A red cap was added because programmers found it difficult to create the hair movement that would occur when the character jumped.

The hat has appeared with Mario ever since then, but was unimportant until Super Mario 64. This was the first game in which Mario could lose his hat. When the hat was lost (by having it stolen by a Ukiki or Klepto or blown off by a gust of wind), Mario would take more damage when attacked. The same happened in Mario's next platformer, Super Mario Sunshine, but with the added effect of gradually losing health.

In the remake of Super Mario 64, Super Mario 64 DS, a Toad revealed that the cap that Mario wears is special and if were to get blown off of Mario, he would have nothing but bad luck. As hinted in Super Mario 64 DS, Mario's hat may be a source of his strength.

Another sign of that cap's importance to Mario is at the end of Super Mario Galaxy 2, when the Baby Luma takes Mario's cap as a souvenir before returning to the Comet Observatory. Mario was shocked about losing his cap at that point.

Versions
In Super Mario 64, Mario has four different types of hats: the Wing Cap (which enables Mario to fly), the Metal Cap (which enables Mario to walk underwater and to walk through fire), the Vanish Cap (which enables Mario to walk through certain walls) and his regular hat. While these powers were dispersed amongst Mario and his companions in Super Mario 64 DS, Mario's Hat gained a new ability: when worn it could turn Luigi, Yoshi or Wario into Mario. If Mario loses his hat he can't fly.

Additionally, due to certain glitches in Super Mario 64, Mario could end up with more than one hat, and could use the duplicate as an effective weapon. In Super Mario 64 DS, if Mario gets another hat, he instead gets an extra life.

Trivia

 * In Luigi's Mansion, after Luigi scans the washing machine, it states that Luigi handwashes his hat while Mario just tosses his in the washer.
 * Also in Luigi's Mansion, Mario's hat is one of the many collectibles belonging to Mario. Mario has two hats through the game, as he wears his throughout the entire game (even while Luigi or Madame Clairvoya is in possession of the collectible hat).
 * Mario's Hat appears as an item in Nintendogs that the player's dog can wear.
 * Club Nintendo of North America released a replica of Mario's cap at the end of the 2009 Club Nintendo year as one of two rewards Platinum members could choose to receive.
 * In the game New Super Mario Bros. Wii, an Easter egg allows Mario to remove his hat when he gets 99 lives, though he doesn't die faster and still does the victory animation at the end of a level as if his hat were still there.
 * The players can buy and wear Mario's Cap in Animal Crossing: City Folk.