User summary (details from Japanese Wikipedia):
A highly typical "right-scrolling action maneuver arcade" game from 1986. The main character is a prehistoric human supposed to save his sweet heart from monsters. The player jumps over boulders and throw stone axes at monsters, sometimes riding on a skateboard, trying to reach the stage end.
Wonder Boy was the first in a series of games with a lot of naming confusion. As the arcade was published by Sega, the game was ported to the SG-1000 and later Sega Mark III (Master System, here named "Super Wonder Boy" to separate from the SG1000 port), and several other 8-bit home systems, but Sega didn't allow for the name to be used for other ports. Westone still owned the code, and the game was ported to the Famicon under the name "Takahashi's Adventure Island" (in the West "Adventure Island) and published by Hudson Soft. This "Adventure Island" spawned a series in itself, but the first game was using the same code as the Wonder Boy game.
The Wonder Boy arcade game was sequelled by a unique arcade RPG adventure called "Wonder Boy in Monster Land", which also saw strange re-namings for the home ports. A third arcade, Monster Lair, shared the name "Wonder Boy III" with the "Dragon's Trap" Master System game only released in the West. See The Wonder Boy series entry for details.
Source: Wikipedia, "ワンダーボーイ_(ゲーム)," available under the CC-BY-SA License.