What is the D in a white circle on the gear selector indicator on 1992 Ford Ranger? It is followed by D 1 2 3?

What is the D in a white circle on the gear selector indicator on 1992 Ford Ranger? It is followed by D 1 2 3?

Read more: What is the D in a white circle on the gear selector indicator on 1992 Ford Ranger? It is followed by D 1 2 3?