What is polyfil?

Where did the polyfill come from and how did the term form? This happened earlier, in 2009, when I was busy writing the book “Introducing HTML5” (“Introducing HTML5”). Sitting in a coffee shop (like you probably now), I tried to find a suitable word with which you can associate “modeling the API of an interface using JavaScript (or Flash, or something else) for a browser that doesn’t have one at that.” . In my understanding, “shim” (* Shim is an interlayer. Code unifying browser work that implements missing or normalizes existing support.)

Means a code fragment (“interlayer”) that is added to the required place, which is able to implement a separate functionality, but in this case we usually deal with our own API. I meant something that you can just plug in and it will do its job quietly. (Remember the old acquaintance “shim.gif” that required you to insert the image needed to fill in the empty tabular td cells? So I wanted something like this, but working automatically, not requiring my participation.) Continue reading →