The difference between bubble and squeak and colcannon is colcannon is a more straightforward mixture of mashed potatoes and cabbage and often contains other ingredients like bacon or onions.
Bubble and squeak is often made with leftover vegetables and often from a roast dinner and is fried into patties.
Both are dishes made with mashed potatoes and cabbage though.
Colcannon tastes like mashed potatoes with a rich, buttery taste and it's very filling with slight bits of textural differentiation from the greens.
Colcannon and champ are both favorite dishes of Irish mashed potatoes.
And they are both similar, although champ often tends to feature spring onions, or scallions alone.
Colcannon adds cabbage, leeks or kale.
Champ is basically mashed potatoes with chopped spring onions (scallions) and milk.
Colcannon is also Champ with the addition of cabbage and sometimes some herbs.
The word colcannon is derived from the Gaelic term cal ceannann, which means "white-headed cabbage".