Smoke is a flavor. So is char. However, when we grill to cook, I believe that by and large we attend to these two less as flavors and more as either an aroma or an optic. For example, “Look at the nice char on that steak.”
Another enormously important and intricate flavor that we often confuse with a simple char is the so-called caramelization of sugars and amino acids on grilled foods called the Maillard reaction, named after its discoverer, French scientist Louis Camille Maillard. Nearly anything brown or dark brown on a cooked (baked, fried, sautéed, grilled, seared, “browned,” roasted, deep-fried, even dried) food is a result of the Maillard reaction. It produces complex flavors, aromas and background tastes, especially umami.
I say “so-called” caramelization because to caramelize anything is, in essence, to darken merely its sugars, not its amino acids. The Maillard reaction also darkens the latter.