Horizontal position

Horizontal position means the way something is lying flat on the ground or on a surface like a table. Imagine you have a toy car and it's laying flat on the floor with its wheels touching the ground. The car is said to be in a horizontal position because it's laying flat and its wheels are on the same level as the floor.

Another example is how you lie down in bed. When you're lying flat on your back, your body is in a horizontal position. This means your head, back, and feet are all on the same level, or parallel to the ground.

So, Horizontal position is just a fancy way of saying that something is lying flat and its top, bottom, left, and right sides are all on the same level like a picture hanging on the wall, a book lying on a table, or a table itself.