First of all, I would strongly recommend you read Doug Crockford’s, JavaScript: the Good Parts. JavaScript has a lot of quirks and rough edges, but please do no

First of all, I would strongly recommend you read Doug Crockford’s, JavaScript: the Good Parts. JavaScript has a lot of quirks and rough edges, but please do not try to use a language in a professional capacity without learning it first. To be fair, JavaScript pretends to be Java just enough to invite all this ill-advised behavior. To answer the question fully: JavaScript arrays are really just plain objects. All objects in JavaScript are simply associative arrays, and all associative arrays are string indexed. So, subscripting always causes a string conversion. The Array class provides some convenience methods with .push() .pop() to gloss over this fact, but arrays are really no different than other objects.