Yoshi

(sometimes specified as Green Yoshi) is one of the heroes of Mushroom World and an ally of Mario. He is a member of the Yoshi race and has aided his brethren in saving their homeland on multiple occasions. Yoshi has also saved other kingdoms from the villain Bowser as well. In his youth, Yoshi managed to rescue and protect Baby Mario and Baby Luigi from the wrath of Kamek and the Koopa Troop. Yoshi made his very first appearance in the Super Mario World level, Yoshi's Island 2. Yoshi, like all other Yoshi's, has a large nose region, a row of red spines along his head, a saddle on his back, which is used by Mario and the gang when being rode on, and a long sticky tongue. The green dinosaur typically wears orange shoes in recent games, but he originally wore brown shoes and also red shoes in a few appearances. Although Yoshi normally has green skin, he has been known to change his colour. For example, in Super Mario World, Yoshi could become blue in colour after collecting a pair of Yoshi's Wings (he would stay green in the GBA remake). In fact, Yoshi would become a literal Blue Yoshi, providing Yoshi with the same strengths and weaknesses as a Blue Yoshi. Yoshi would not return to his original color unless he ran off and became re-encased in a Yoshi Egg.
Like other Yoshi's, Yoshi has a long, sticky tongue that he uses to eat almost anything, even things much larger than himself. Yoshi can transform the enemies and other objects he eats into eggs, which he can then use as projectile weapons. The green dinosaur has pinpoint accuracy, allowing him to conserve his egg supply during heated battles. During the events of Super Mario World 2: Yoshi's Island, Yoshi could keep up to six eggs at a time.
Interestingly, Yoshi can also transform things that he eats into other objects. For example, in Super Mario World, after Yoshi ate an enemy, one Coin would be added to Mario's coin total. The green dinosaur could also transform berries into eggs. However, instead of using them as projectiles, these eggs would break apart and reveal items, including Super Mushrooms and strange, smiling clouds that would drop coins. In Super Mario RPG, Yoshi could eat enemies to produce eggs that would break apart to reveal a variety of helpful (and often rare) items.
Yoshi has a hard time swallowing Koopa shells. In fact, in Super Mario World 2: Yoshi's Island, the green dinosaur simply had to spit out the Koopa shell before he could eat another enemy. In Super Mario World, Yoshi could eventually swallow a Koopa shell, but could also use Koopa shells to boost his own abilities. While Yoshi could only spit out a green shell, if Yoshi spit out a red shell, the green dinosaur would instead shoot three large fireballs. A yellow shell would allow Yoshi to create sand clouds whenever he jumped and hit the ground, destroying nearby enemies. A blue shell provided one of the two ways to turn Yoshi into his Winged Yoshi form, allowing him to fly for a limited amount of time. However, if a shell were left in Yoshi's mouth for too long, he would inevitably swallow the shell and as such lose any abilities he may have possessed.
Yoshi is very proficient with Jump and Ground Pound, abilities, rivalling the capabilities of world-renown jumper Mario. However, in Super Mario World, Yoshi's jump attacks were much more powerful than Mario's normal jump attacks. Yoshi could destroy most enemies in one hit (i.e. a Koopa would be completely destroyed, not sent flying out of its shell). As such, Yoshi's jump had the same power as Mario's special Spin Jump technique. The green dinosaur is also a master of the Flutter Jump technique, allowing him to jump with incredible horizontal distance.
Yoshi is a speed character in several sports games, such as the Mario Tennis series, which shows that he is a fast runner. However, he isn't particularly fast in every game, such as Super Mario 64 DS where his speed is the same as Mario's (according to the instruction booklet).
Yoshi is an extremely friendly individual who always lends a helping hand to those in need. He could be considered a hero and has helped his friends, defeated the evil King Bowser Koopa, and saved his island more than once. Once Yoshi takes on a task, he does not give up until he completes it. Yoshi never backs down at defending his homeland and friends. He is also very courageous, allowing the green dinosaur to stand and fight enemies much larger than himself, including Yoob, an enlarged Bowser, Nep-Enuts, Tap-Tap the Golden, and the gigantic Baby Bowser. As a result of this courage, Yoshi often takes on a leadership position to the Yoshi clan, although Yoshi has no official political status (unlike the Village Leader from Lavalava Island). In fact, when Yoshi was offered a leadership position during the events of Super Mario RPG: Legend of the Seven Stars, the humble dinosaur declined the position. Like Mario, Yoshi has a large appetite. While Yoshi mostly eats fruits (mainly melons), he will eat almost anything including enemies (except peppers and certain inedible enemies). Yoshi also has bad chemistry with Magikoopa, likely due to he and Kamek's history. He is sometimes portrayed as the comic relief, though lesser so than Luigi.