> For the complete documentation index, see [llms.txt](https://cathyatseneca.gitbook.io/data-structures-and-algorithms/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cathyatseneca.gitbook.io/data-structures-and-algorithms/sorting/simple_sorts/insertion_sort.md).

# Insertion Sort

The insertion sort algorithm works by looking at the array as if it is being filled in. The idea is that the array starts off in the first iteration as if it has only one element in it. The numbers that come after are then inserted into the "array" at the correct position. This is continued until all values in the entire array have been properly "inserted"

```c
void insertionSort(int arr[],int size){
    int curr;
    int i,j;
    for(i=0;i<size;i++){
        curr=arr[i];
        for(j=i;j>0 && arr[j-1] > curr;j--){
            arr[j]=arr[j-1];
        }
        arr[j]=curr;
    }
}
```

[Insertion sort animation: http://cathyatseneca.github.io/DSAnim/web/insertion.html](http://cathyatseneca.github.io/DSAnim/web/insertion.html)