After learning common sorting algorithms, feel like demonstrating them using not only brief description but also animated demos.

Here contains 6 sorting algorithms, half are simple, half are advanced:

• Bubble sort
• Selection sort
• Insertion sort
• ~
• Merge sort
• Shell sort
• Quick sort

Bubble sort

This maybe the simplest sort, notoriously slow though.
Suppose we were arranging a queue of baseball players by their height. Start from leftmost.

1. compare two players

2. if the one on the left is taller, swap them. Otherwise, no action.

3. move one position right

Selection sort

Start from leftmost too.

1. look for shortest player from current position to right

2. swap shortest player with the player at current position

3. move one position right

Insertion sort

In most cases, this is the best of elementary sorts. It's about twice as fast as the bubble sort.
The steps is somewhat complicated than sorts above.Start from leftmost.

1. partially sort left players

2. choose the first unsorted player as marked player

3. shift the players shorter than marked player to right

4. insert marked player into the previous position of first shifted player.

Merge sort

The heart of the merge sort algorithm are the merging of two already-sorted arrays and recursion.

As shown in picture, main steps are:

1. Recur to split numbers into 2 parts

2. merge 2 parts

Shell sort

The name "Shell sort" is named for Donald Shell, who discovered it. It's based on insertion sort, but adds a new feature that dramatically improves the insertion sort's performance.

Main steps

1. divide array into groups by interval(3 for example) and sort them continously until all items are divided and sorted.

2. diminish the interval and continue to divide and sort until the interval becomes 1.

Quick sort

In the majority of situations, this is the fastest sort.

1. choose a pivot(rightmost item)

2. partition the array into left sub array(smaller keys) and right sub array(larger keys)

3. recur step2 to left sub array and right sub array