There are five "ranges". Sorted by distance, they are:
1 Weapons range
2. Kicking range
3. Punching range
4. Grappling on your feet
5. Grappling on the mat or ground
Notice there are two grappling ranges. When you are grappling on your feet, there is typically a little less of your body in contact with their body than when you are grappling on the ground. Thus, grappling on the ground is a "closer" range than grappling on your feet.
Each thing taught is for a specific range, and is generally not well suited for a different range.