Smoke markers: "distinct"

SMOKE CLOUD POWER: Minimum range 4. Generate up to 6 Smoke terrain markers, one at a time, in distinct squares within range. Other than the first, each marker must be adjacent to at least one other, and at least one must be within line of fire. Opposing characters occupying one or more of these markers modify attack -1. At the beginning of your next turn, (even if this is lost) remove them.

What does "distinct" here mean? Are they trying to say you can't place a smoke marker on a smoke marker?