“Flour” as an ingredient in modern recipes is also presumed to be plain, white flour — called “plain flour” in the UK, and “all-purpose” in North America.
Wheat flour does, though, come in different forms and strengths. There is “stronger” flour which will develop more gluten, which is called “bread flour.” There is durum wheat flour and semolina for pastas, and whole wheat flour for breads,
Some wheat flour comes with additives. Self-rising flour comes with baking powder already mixed into it; French bread flour has in it a small amount of ground, dried broad beans (fava beans.)
Whenever any of the above specialty wheat flours are required, the recipe will specify it.
For a fuller discussion of flour and flours, see the main entry on flour.