Array
In one line
An array is an ordered list of values stored under a single name, accessed by their position (index).
In simple words
An array lets you store multiple values in a single variable, in a specific order. Each value is called an element, and you access it by its position (index). In most languages, indexing starts at 0 — the first element is at index 0, the second at index 1, and so on.
Arrays are perfect for collections of related data: a list of scores, a set of user names, the pixels in an image. You can loop over an array to process every element, add or remove items, and search for specific values.
Arrays have a length (number of elements) and support operations like push (add to end), pop (remove from end), and slice (extract a portion). They are one of the most used data structures in programming.
Example
let fruits = ["apple", "banana", "cherry"];
console.log(fruits[0]); // "apple" (index 0)
console.log(fruits.length); // 3
fruits.push("date");
console.log(fruits); // ["apple", "banana", "cherry", "date"]Arrays are indexed from 0. .length gives the count, and .push() adds an element to the end.
How it works
- Create an array with
[value1, value2, ...]. - Access an element by index:
arr[0]is the first element. - Modify an element:
arr[1] = newValue. - Iterate with a loop:
for (let i = 0; i < arr.length; i++). - Use methods like
push,pop,slice,map,filterto transform the array.
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