what is time complexity of insertion sort

1Time Complexity is: 
2If the inversion count is O(n), 
3then the time complexity of insertion sort is O(n).
4
5Some Facts about insertion sort:
61. Simple implementation: Jon Bentley shows a three-line C version, and a five-line optimized version[1]
72. Efficient for (quite) small data sets, much like other quadratic sorting algorithms
83. More efficient in practice than most other simple quadratic (i.e., O(n2)) 
9algorithms such as selection sort or bubble sort
104. Adaptive, i.e., efficient for data sets that are already substantially sorted: the time complexity is O(kn)
11when each element in the input is no more than k places away from its sorted position
125. Stable; i.e., does not change the relative order of elements with equal keys
136. In-place; i.e., only requires a constant amount O(1) of additional memory space
14Online; i.e., can sort a list as it receives it