A Shiny Bidoof character is a version of the Pokémon Bidoof that has a different coloration than other Bidoofs. While Bidoofs are normally brown, a Shiny Bidoof is light brown. A Shiny Bidoof also has a purple snout, while regular Bidoofs have black snouts.
The term "Shiny Pokémon" is used by fans to describe a Pokémon with alternate colorations. This term came about due to the fact that when a Pokémon with an alternate coloration enters battle, some gleams of light surround the Pokémon. Eventually, the term was used in the Pokémon Black and White game, meaning it was canon in the world of Pokémon. Shiny Pokémon have the same statistics as regular Pokémon. The chances of finding or hatching a Shiny Pokémon change in each generation of Pokémon. As of Pokémon X and Y, there is a 1/4096 of a Pokémon being shiny. Shiny Pokémon evolve into other Shiny Pokémon. For example, a Shiny Bidoof will evolve into a Shiny Bibarel.
A Bidoof is a normal type Pokémon that first appeared in the Sinnoh region of the fictional world of Pokémon. A Bidoof evolves into a Bibarel at level 15. It is usually a common Pokémon in the wild. Since many Bidoofs appear in the wild, it may be easier for players to find and catch a shiny one.