[WiseWeasel]

The way I would describe an array to a novice is that it's a more complex and potentially useful type of variable, similar to the ones you've been making so far, only instead of having a single "slot" for data, they are organized in a way that allows for multiple slots for information, and you can reference each slot by their position in the array, starting with position 0 (0, 1, 2, etc. describing the first, second and third. etc. positions in the array).

An array is a variable declared with square brackets around all the data, with a comma in between (delimiting) each positioned slot of data.

Example:

    var array = ["data1", "data2", "data3"]

In this case, we've created an array containing text strings. It could just as easily contain integers, or as you will see demonstrated a little later in the course, other variables, including other arrays.

Then, in order to retrieve or modify a piece of information from the array, you reference the array variable with the array position you want in square brackets.

Example: To get the "data1" string from the above array, use the variable like this:

    array[0]

To get an alert dialog with the "data2" string, the code would look like:

    alert(array[1])

You can easily modify a piece of data in the array using this technique. For example, to change the string "data3" in the array to "third", the code would be:

    array[2] = "third"

If you would like to add a new piece of data to the array, you could do the following:

    array[3] = "fourth"

Note that this would require that you know the size of the array and that the position [3] is an available slot. A simpler method of adding data to an array is to use the .push function as such:

    array.push("fourth")

[buff-a]

I need some milk! Let me add that to my shopping array.

Back in the real world, I see non techies deal with lists every day. Ordered lists. Given a list, with numbers in the margin, they can easily answer "Who came first?" or "What's next on the list?", or "What's item 5 on the agenda".

But noooo. We have to call them arrays. Lists are something else. o_O

The way I would describe an array to a novice is that it's a more complex and potentially useful type of variable

Fuck me no!!!! Shut up Moss!

[WiseWeasel]

That's because arrays do get more complicated than flat lists like the example I gave above. You can actually have multiple organized data points in each position of the array as well, making arrays function more as a 2D relational database than as a flat list of data.

For example, I could make an address book array with multiple data points as such:

    var addressbook = [{"firstname": "John", "lastname": "Doe", "phone": "555-555-5555", "email": "[e-mail]"}, {"firstname": "Jane", "lastname": "Smith", "phone": "666-666-6666", "email": "[e-mail]"}]

Then, I can retrieve a piece of information like Jane's phone number like this:

    var janesnumber = addressbook[1].phone

Arrays are very powerful tools, especially once you start referencing other arrays in them, as it allows complex organization of data without always needing to resort to a database solution, with a whole new language to learn.

[zds]

Thanks so much for the feedback. This lesson needs some improvements and we'll be shaping it up over the next few days.