It was some time since I heard about Construct, a HTML5 game editor that uses WebGL rendering.
Construct2 is very efficient and easy to handle: its user interface consists of a "visual" part (objects and layers) and of a "programming" part (actually events that can be manipulated by drag and drop).
Newcomers didn't have to fear: the adjustment period is fast and there are a lot of sprite behaviors ready-to-use to easily build platform games and shooters. Experienced programmers will not be left hungry, because the application also proposes to implement your own code.
To get the foot in the door, I realized a first game called "iCatch". It is above all a test to see if it was possible to achieve something other than a shooter or platform, and the answer is yes.
So I will just say that if you have any desire to make your own game, Construct is made for you!