Reference documentation and lots of examples are available directly on the [website](http://p5js.org/).
Ranked in these QuestionsQuestion Ranking
Pro Operator overloading
Pro Geometric Tests
An almost-unique feature: can test geometry if contains(), isInside() or intersects() one other object. Offers even hit-testing methods!
Pro Behaviours handled by objects
Example: each swimming tadpole follows its own behavior
These features make it easier to create objects that can act autonomously with complex behaviors. This makes Paper a good choice for particle effects and game development.
Pro Object constructors
Elements all have the option of being created with a hash of properties which promotes clean, concise, and contextually local coding practice.
Pro Good for making games
Paper uses a frame based approach to rendering the canvas. This makes it conceptually easier to create objects with animations and behaviors that interact and perform with other objects.
Along with Paper's approach to creating and managing objects this makes Paper especially good for creating applications with complex behaviors with many elements doing different actions at once, and makes it a good choice for making games.
Pro Accessible documentation
Reference documentation and lots of examples are available directly on the website.
Pro Great community
p5 users benefit from the Processing community's 15+ years of growth and discovery. Processing code can easily be converted to p5.
Pro General programming concepts
As a continuation of the Processing project, this frameworks helps in understanding the general programming concepts that goes beyond drawing (connecting electronics, using sounds or the webcam etc),
Pro Easiest to learn to obtain high grade results
In a few days any body can understand extremely complex figures in a few minutes.
Pro A lot of YouTube tutorials
Con Limited to single instance
The code is written in a way that everything is global and limited to a single instance, there is no clean way to use 2 separate instances in the same page
Con Not supported in older browsers
Paper.js runs on top of HTML5 Canvas, which is not supported in older browsers.
Con No built-in rendering
If looking for something to build UIs with or similar, one might be disappointed by the lack of any pre-defined UI element objects and such in p5.js. One has to write all the rendering code for any objects one includes, integrating it appropriately with the loop.