Answer:
A bubble sort is a sort where adjacent items in the array or list are scanned repeatedly, swapping as necessary, until one full scan performs no swaps.
Advantage is simplicity.
Disadvantage is that it can take N scans, where N is the size of the array or list, because an out of position item is only moved one position per scan. This can be mitigated somewhat by starting with a swap gap of greater than one (typically N/2), scanning until no swaps occur, then halving the gap and repeating until the gap is one. This, of course, is no longer a bubble sort - it is a merge exchange sort.