Yoshi has a variety of abilities that stand out relative to other characters in the Mario series. Yoshi's prehensile tongue can extend a considerable distance to eat enemies, grab distant objects, or act as a grappling hook to access otherwise out-of-reach areas. After eating an enemy or object, Yoshi may either spit it out as an attack, or swallow it to instantly turn it into a distinctive spotted egg; eggs can then be thrown at distant targets to collect or damage them, and depending on the game they either explode on impact or ricochet off surfaces. Another signature technique is the Flutter Jump, where Yoshi quickly flaps his arms and legs to slow his descent from a jump or even gain height in midair. Yoshi is also a noted user of the Ground Pound, which involves dropping bottom-first after a jump in order to destroy blocks or damage opponents. Yoshi's large nose unsurprisingly allows for the detection of hidden collectibles as well as flowers by smell and, as demonstrated in the Super Smash Bros. series, may be used as an offensive weapon. Yoshi can form an egg around himself, which can be used for protection as a shield against attacks or for mobility by rolling or launching himself. Finally, in sporting events, Yoshi's special shots tend to leave a rainbow trail behind the ball or involve rainbows in some other way.

The Yoshi species appear in a variety of colors. This is generally a cosmetic difference used to differentiate individuals. However, the color of a Yoshi can also provide additional offensive or movement abilities, such as fiery breath, wings, balloon-like inflation, or juice-spitting. In some games this is a characteristic of the Yoshi's natural colour, while in others it is a temporary status gained by eating certain fruit or flowers. Yoshis of various colors appear often in multiplayer games as alternate choices, which may or may not have statistics unique from the default green color.

In games where the player can ride Yoshi, he acts as an extra hit point; taking damage causes the player to be knocked off Yoshi instead of any other negative effects. This makes Yoshi start to run around haphazardly until he is remounted or falls off-screen. Yoshi is otherwise indestructible; he can freely walk over spikes, does more damage to enemies when jumped on, and can take any number of hits without additional penalty. Combined with his other unique powers, this makes him very strong in levels designed for Mario's abilities, while a level designed for Yoshi may be overly difficult for Mario alone. As a result, Yoshi's presence tends to be limited to certain levels; for example, in Super Mario World he is not allowed in haunted or castle levels (explained in-universe by him being scared of such areas). While riding Yoshi, bongos or other thematically-appropriate percussion instruments are added to the level's background music.

In the SNES and early N64 eras, Yoshi's vocals consisted of record-scratching noises for positive interactions and whistling noises for negative interactions. Yoshi's Story gave Yoshi a new voice, provided by the game's composer Kazumi Totaka, consisting of high-pitched babyish squeals and intelligible words including "Yoshi" and "Nintendo". [14] This new voice appears in Super Smash Bros., Mario Tennis, and all games since and including Super Smash Bros. Melee. Yoshi retains the classic record-scratch sound for when he is mounted.

Yoshis' language skills are inconsistent. In some games, they speak the same language as all other characters. In others, they are shown with their speech in parentheses to imply speaking a different language that is translated for the player to read. Sometimes they are shown only speaking the repeated word "Yoshi". Whether other characters can understand Yoshi speech is also inconsistent.

Yoshi first appeared in Super Mario World as a dinosaur whom Mario or Luigi could ride on in Dinosaur Land. Yoshi could also eat enemies when Mario or Luigi punched Yoshi in the back of the head.[10] This game spawned a chronological prequel titled Super Mario World 2: Yoshi's Island for the Super NES, in which the player must control various Yoshis in order to keep Baby Mario out of harm's way through the game. This led to a spin-off series of games, Yoshi's Safari for the Super NES, Yoshi's Story for the Nintendo 64, Yoshi's Universal Gravitation for the Game Boy Advance, Yoshi's New Island for the Nintendo 3DS, and a number of games for the Nintendo DS, including Yoshi Touch & Go, Yoshi's Island DS, and Super Mario 64 DS. In 2015, an original Yoshi game was released on the Wii U called Yoshi's Woolly World. Yoshi also appeared in the 2017 game, Super Mario Odyssey. In 2019, Yoshi's Crafted World was released on the Switch.

Although introduced on the Super NES in 1990, Yoshi was also the star of two self-titled games for the original NES released in 1992 and 1993: Yoshi and Yoshi's Cookie, respectively. Both of these games were released for the Game Boy as well. Yoshi appeared as a supporting cast member in Mario is Missing for NES, SNES, and MS-DOS in 1993.[15] Yoshi appeared in Super Mario 64 as a non-playable character who could be seen upon 100% completion of the game and be briefly visited after. Yoshi also appeared in the DS remake as a playable (and starring) character.

In Super Mario Sunshine for GameCube, Yoshis could be ridden on by Mario in the same fashion as in Super Mario World. However, in this game, the only Yoshis available are orange, pink and purple, each of which have slightly different powers and are obtained upon bringing certain tropical fruit to their eggs. Yoshis appear in New Super Mario Bros. Wii and New Super Mario Bros. U, with each one functioning much like Yoshi did in Super Mario World, but with the added ability to use the Flutter Jump and Ground Pound like in the Yoshi's Island games. New Super Mario Bros. U also notably features the return of baby Yoshis, who were last seen in Super Mario World.

Yoshi also appears in Super Mario Galaxy 2 with the Flutter Jump and Ground Pound. However, certain foods grant additional powers and change Yoshi's signature green color to the color of the fruit: the red Dash Pepper grants super speed, the light blue Blimp Fruit allows Yoshi to float upward, and the yellow Bulb Berry reveals hidden platforms.[16] Yoshi was intended to appear in the original Super Mario Galaxy, but was removed because it would be, "too much all at once."[17]

The Yoshi species makes its Paper Mario series debut in the fifth chapter of Paper Mario when Mario comes across a village of Yoshis and rescues a group of Yoshi kids after they become lost in the surrounding jungle outside of the village. In the sequel Paper Mario: The Thousand-Year Door Mario rescues a Yoshi egg that hatches into a baby Yoshi, who then joins his team during the third chapter of the game and can be named upon doing so. The color of the Yoshi depends on the amount of time that passes between rescuing the egg and the egg hatching, with the timer being reset after 20 minutes have passed. Unlike in some games, the Yoshi's coloration is merely cosmetic. The Yoshi has the only attack that can damage the two Iron Clefts known as the "Armored Harriers" introduced in the same chapter (even a perfect Superguard or the "Piercing Blow" badge won't scratch them). The Yoshis appear multiple times as non-player characters throughout the Mario & Luigi series, having a whole club dedicated to them in Mario & Luigi: Superstar Saga.

Yoshi and his species make numerous appearances in Super Mario Maker. In the Super Mario Bros. style they have a total of five Mystery Mushroom costumes between them, based on their appearances in Yoshi's Island and Yoshi's Woolly World. In the Super Mario World and New Super Mario Bros.