Mario, Luigi's brother, is an italian plumber. He's the most popular videogame-character of the world and the mascot of Nintendo. His typical slogans are „Mamma mia“ and „It's-a-me, Mario“, and his Character is helpful and adventurous. Mario was the first time a naming protagonist of the game „Mario Bros.“ in 1983. After that, there were many Mario-Games for the different Nintendo Consoles.
Luigi is the younger brother from Mario. Like his brother, he's also a plumber, but he is taller and slimmer than Mario. In many Games, he can jump higher and wider than him. His first naming Game was Luigi’s Mansion, and after that, many other Games came with Luigi as Main character.
Wario, Marios Cousin, was first a money greedy opponent of Mario. His Name is Mix of the name „Mario“ and the japanese adjective „warui“ what means "bad", so his name mean „bad Mario“. His appearance is also based on Mario, but Wario is more muscular. His first game was „Wario Land – Super Mario Land 3“. His Character is egoistic and deceitful, but in some Games, he's also a friend of Mario und co.
Waluigi was created to give Luigi also a personal opponent, so he is the „bad Luigi“. He's the Cousin of Mario and Luigi, and the Friend/brother of Wario. His Logo is an upturned „L“, like Luigi's logo, which is the „L“. He has got a similar character like Wario.
Princess Peach is the Princess, who is always kidnapped by Bowser. So Mario's Job is, to save her every time. Her personality is always polite and happy.
Princess Daisy is the Cousine of Princess Peach and the Girlfriend from Luigi. Their Relationship is similar to the relationship of Mario and Peach. Daisys Character is energic and happy.
Yoshi is a green Dinosaur and a friend from Mario. He is popular for his very long tongue, which he can swallow his opponents. Sometimes that gives him special skills. Yoshi is friendly and helpful, and in some Games, he has different Colors.

Toad is very small, and his apperance is based on a mushroom. He is friendly and very adventurous, and became popular through Super Mario Bros., where he stoodd at the end of every level and said „Thank you Mario! But our princess is in another castle!“.

There are also some colored Toads, which are tips or an alternate character, like the toads in Super Mario 64 or in Super Mario 3d Land.

Toadette is the female Toad, and is also the Girlfriend of Toad. She's got some appearances in some games.

Donkey Kong (also DK) was one of the first characters from Nintendo. In his own game Donkey Kong, Mario still called Jumpman. He had his own series.
Diddy Kong is Donkey Kongs best Friend. He helps Donkey Kong at many Adventures and is also another character in different Games.