Insertion Sort is an efficient sorting algorithm used for general-purpose sorting. It is a comparison-based sorting technique similar to bubble sort and selection sort. The algorithm works by iterating through an unsorted list of elements and comparing each element to the elements before it, starting at the first position of the list. If an element is found to be smaller than the element before it, the algorithm swaps the two elements and continues iterating forward until the next swap is not required.
Insertion sort is often used when the input size is relatively small as it requires fewer comparisons than other algorithms like quick sort. It is usually preferred by developers as it is considered to be stable and more efficient than bubble sorting techniques. One of the main advantages of insertion sort is its ability to sort partially-sorted data sets with minimal number of comparisons.
Insertion sort has a time complexity of O(n2) when sorting an array of n elements, meaning the execution time increases quadratically with the input size. Insertion sort is not suitable for large data sets as it is considered to be less efficient than quick sort and merge sort algorithms.
Despite its limitations, insertion sort is a useful sorting technique for sorting partially-sorted data sets or small data sets. It offers a simple and intuitive sorting approach compared to other comparison-based sorting algorithms which can be helpful for educational and debugging purposes.