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freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/access-array-data-with-indexes.md

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---
id: 56bbb991ad1ed5201cd392ca
title: Access Array Data with Indexes
challengeType: 1
videoUrl: 'https://scrimba.com/c/cBZQbTz'
forumTopicId: 16158
dashedName: access-array-data-with-indexes
---
# --description--
We can access the data inside arrays using <dfn>indexes</dfn>.
Array indexes are written in the same bracket notation that strings use, except that instead of specifying a character, they are specifying an entry in the array. Like strings, arrays use <dfn>zero-based</dfn> indexing, so the first element in an array has an index of `0`.
<br>
**Example**
```js
var array = [50,60,70];
chore(learn): audit javascript algorithms and data structures (#41092) * chore(learn): audit basic algorithm scripting * chore(learn): audit basic data structures * chore(learn): audit basic javascript * chore(learn): audit debugging * chore(learn): audit es6 * chore(learn): audit functional programming * chore(learn): audit intermidate algorithms * chore(learn): audit js projects * chore(learn): audit object oriented programming * chore(learn): audit regex * fix(learn): remove stray . * fix(learn): string to code * fix(learn): missed some * fix(learn): clarify strings Based on Randy's feedback, clarifies string instances where quotes were removed in favour of back ticks. * fix: apply suggestions - thanks Randy! :) Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: non-suggestion comments * chore(learn): remove comments from codes Removes the comments from the description and instruction code blocks to ensure that all relevant information is translatable. * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: revert crowdin fix * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/mutations.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * chore: change voice * fix: Christopher Nolan * fix: expressions would evaluate * fix: will -> would * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: to work to push * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-with-javascript-for-loops.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
2021-03-02 16:12:12 -08:00
array[0];
var data = array[1];
```
chore(learn): audit javascript algorithms and data structures (#41092) * chore(learn): audit basic algorithm scripting * chore(learn): audit basic data structures * chore(learn): audit basic javascript * chore(learn): audit debugging * chore(learn): audit es6 * chore(learn): audit functional programming * chore(learn): audit intermidate algorithms * chore(learn): audit js projects * chore(learn): audit object oriented programming * chore(learn): audit regex * fix(learn): remove stray . * fix(learn): string to code * fix(learn): missed some * fix(learn): clarify strings Based on Randy's feedback, clarifies string instances where quotes were removed in favour of back ticks. * fix: apply suggestions - thanks Randy! :) Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: non-suggestion comments * chore(learn): remove comments from codes Removes the comments from the description and instruction code blocks to ensure that all relevant information is translatable. * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: revert crowdin fix * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/mutations.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * chore: change voice * fix: Christopher Nolan * fix: expressions would evaluate * fix: will -> would * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: to work to push * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-with-javascript-for-loops.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
2021-03-02 16:12:12 -08:00
`array[0]` is now `50`, and `data` has the value `60`.
**Note:** There shouldn't be any spaces between the array name and the square brackets, like `array [0]`. Although JavaScript is able to process this correctly, this may confuse other programmers reading your code.
# --instructions--
Create a variable called `myData` and set it to equal the first value of `myArray` using bracket notation.
# --hints--
The variable `myData` should equal the first value of `myArray`.
```js
assert(
(function () {
if (
typeof myArray !== 'undefined' &&
typeof myData !== 'undefined' &&
myArray[0] === myData
) {
return true;
} else {
return false;
}
})()
);
```
The data in variable `myArray` should be accessed using bracket notation.
```js
assert(
(function () {
if (code.match(/\s*=\s*myArray\[0\]/g)) {
return true;
} else {
return false;
}
})()
);
```
# --seed--
## --after-user-code--
```js
if(typeof myArray !== "undefined" && typeof myData !== "undefined"){(function(y,z){return 'myArray = ' + JSON.stringify(y) + ', myData = ' + JSON.stringify(z);})(myArray, myData);}
```
## --seed-contents--
```js
// Setup
var myArray = [50,60,70];
// Only change code below this line
```
# --solutions--
```js
var myArray = [50,60,70];
var myData = myArray[0];
```