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The browser value of such a property is a Javascript array. Depending on it's pushToServer setting it can watch for granular changes and send granular changes to server (so for example if only one of it's elements has changed it will only send that change to server).

Server side javascript value

There is one difference though. In order to be able to send fine-grained updates to the client/browser, those values are 'watched'. That means that whenever you assign a completely new javascript array directly to the property (or if you assign a new object/array into one element of it or nested on any level), that new value (reference) you assign will not be 'watched' directly; you have to take/read it back from the property (which will give you an equivalent 'watched' value) before using it further in code. Or you can access the value of the property directly every time, not kept as a reference.

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// DO NOT DO IT LIKE THIS
var newPropertyValue = {};
// here you assign a new array to the property
elements.myCustomComponent.myArrayProperty = newPropertyValue;

(...then later on, maybe during another event handler execution...)

// this will modify the value in newPropertyValue but myCustomComponent.myArrayProperty will not be aware of that to send changes to client/browser
newPropertyValue[1] = 5; 

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The server side JS value of such a property is a custom implementation that inherits from the Javascript array prototype - so you should be able to use it just like a normal JS array.
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