What's the difference between an array and a table?

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#1

Very simple question:
What’s the difference between an array and a table?

I’ve seen it used differently, with the API reference stating that it needs an array to be given for a function, and sometimes it needs a table, and yet I can’t seem to find a difference? I’m probably just losing my braincells, but I’m surprised I do not know this, since I started last December.

Thanks.

#2
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#3

There isn’t really a difference, those 2 are basically the same. If you hear someone say this is a table or that is an array etc, they are talking about the same thing pretty much. A datatype that can carry multiple data types like Strings, Integers and Booleans.

#4

Tables is a native datatype that can store values assigned to a non-nil value keys.

Arrays are referring to tables that only stores values using numeric value keys.

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#5

Array = table where the indexes are numbers
Dictionary = table where the indexes are strings (or anything that isn’t a number.)

local array = {
  "String one";
  "String two";
}

print(array[1]) --Expected: "String one"

local dict = {
  ['weapon'] = "Sword";
  ['armor'] = "Silver";
}

print(dict['weapon']) --Expected: "Sword"
print(dict.weapon) --Expected: "Sword"
--Notice how we can use path notation to index keys from our dict, where with the array we have to use a number.
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#6

These terms are often used interchangeably, even though they are not the same thing.

In general programming, an array is defined as a collection of data, all of the same type and with a set number of values. Eg.

int array {40, 30, 20, 10, 0}

This will create an array with a length of 5, and initialize array[0] to 40, array[1] to 30, and so on.
With these kinds of arrays, refering to or attempting to set array[6] would result in an error. If you created an Int array with a string value included, it would also error. Eg.

int array {6, “string”} // This is not an integer value, so my program won’t work!

Roblox does not use typical arrays, it uses a native datatype called a “table”. A Roblox table is still a collection of data, however a table does not have a set number of values on creation and can hold any different types of data in the same table. Eg.

local thisTable = {40, “30”, 20.5, 10, false}

In Roblox, you can refer to thisTable[6] and nil will be returned, or you can set thisTable[6] to a value. There are also other similar datatype such as dictionaries and tuples, you can read up more on them on the web.

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#7

The amount of overexplaining in this thread is crazy.

A table is a data type that can store other data. They are often used to represent objects. Data within a table is accessed using a key. Keys are often strings. A car table, for example, might contain a key “color” that points to the value “red”.

An array is a table where the keys are integers and they’re in order starting at 1. Arrays are often used when the data within the table isn’t standardized. For example, a car table might have a key “PossibleColors” that points to an array “{“red”, “blue”, “green”}”. GetChildren and similar functions return arrays. When you have an array, you normally access the data by iterating over its contents instead of using keys to access it directly.

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