I loved this program as a kid (you can probably tell by my "icon")!
Widget is a "Watcher" that mistakenly gets sent to Earth, along with a Mega-brain unit (who is simply called "Mega Brain"). Mega Brain lives inside Widget's wrist-watch and is meant to help Widget solve the ecological problems (pollution, deforestation etc.) that could "plunge our world into peril". Although Mega Brain (who sometimes also makes new new inventions for Widget) can become easily disorientated and sometimes makes even minor problems more catastrophic.
Along the way, Widget also meets two "earth boys" (Brian and Kevin) as well as an older teenage girl (Christine), who usually try and assist Widget on his various quests and missions.
Of course there are also villains: Mega Slank, or Wratchet - (Wratchet looks like Widget, except in vile villain form), who are constantly causing mischief for our heroes.
During the series run, Widget also visited places such as Australia (the outback - and the Great Barrier Reef), Paris and even the Amazon Rainforest.
Although I think Widget was just another of those so-called "help the planet" type cartoons (much like "The Smoggies" or "Captain Planet), it still remains a cartoon that is still very-much talked about. Though it ended its run more than a decade ago and hasn't been seen on many TV stations since then.