Chapter 7. Arrays
An array is an ordered collection of values.
Each value is called an element, and each element
has a numeric position in the array, known as its
untyped: an array element may be of any type, and
different elements of the same array may be of different types. Array
elements may even be objects or other arrays, which allows you to create
complex data structures, such as arrays of objects and arrays of arrays.
indexes: the index of the first element is 0, and the highest possible
index is 4294967294 (232−2), for a maximum
dynamic: they grow or shrink as needed and there is
no need to declare a fixed size for the array when you create it or to
sparse: the elements need not have contiguous
length property. For nonsparse arrays, this
property specifies the number of elements in the array. For sparse
length is larger than the
index of all elements.