An array is a collection of stored data that can hold values of various data type. Arrays themselves are considered to be a composite data type. Python uses lists as an equalivalent type.
Arrays are often created by using square brackets
 with a comma-separated list of individual elements inside:
array = [element0, element1, element2, element3]
Nested arrays (arrays within arrays) are also possible:
nested = [elementB, elementC] outer = [elementA, nested, element4]
The length of the
outer array is 3 elements-long because the inner
nested array counts as an individual element. By itself, the
nested array is 2 elements-long.
Array elements are usually referenced by an index number, which represents their position in the sequence.
The indices of most arrays start with 0:
groceryList = ["milk", "cookies", "berries", "carrots"] // index: 0 1 2 3
- The first element
"milk"is at index 0.
- The second element
"cookies"is at index 1.
- …and so on.
Arrays in Different Languages
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