Sequentially checks the target value in given list and match found.
Time Complexity:
 best : O(1)
 Worst: O(n)
Space Complexity: O(1)
<pre><code>function linearSearch(arr, target) {
 for (let i in arr) {
 if(arr[i] === target) return i;
 }
return -1;
};

linearSearch([1,2,3,4], 3);
&gt; '2'
linearSearch([1,2,3,4], 5);
&gt; -1
</code></pre>Linear search is best to use while searching in unsorted array.
JS <code>indexOf(), includes(), find() &amp; findIndex()</code> implemented using linear search.

Sequentially checks the target value in given list and match found.

Time Complexity:
     best  :  O(1)
     Worst: O(n)

Space Complexity:  O(1)

```
function linearSearch(arr, target) {
    for (let i in arr) {
        if(arr[i] === target) return i;
    }
return -1;
};

linearSearch([1,2,3,4], 3);
> '2'
linearSearch([1,2,3,4], 5);
> -1
```

Linear search is best to use while searching in unsorted array.

JS `indexOf(), includes(), find() & findIndex()` implemented using linear search.

JS Linear Search

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