This is what I see out my side window mirror when I back into a parking space.
On the left, you can see the white hood of the truck parked to my left as I'm backing into the space.
In the mirror, you get 2 more views of it.
Sometimes it is hard to get your mind wrapped around which view is which and what your own truck is doing.
I guess it is all about perspective.
This mirror has one just like it on the other side and for some odd reason, they are called "West Coast"mirrors.
As I back up, you can also see how close these damn trucks are! Sometimes I think we could all stick our hands out the windows and pass Grey Poupon from truck to truck. That would make a great commercial.
Anyway, back to the photo . . . see that convex mirror below the tall one?
That one gives a better view down the length of the truck and it shows the ground more. It also gives the driver a good view of where their back wheels are meeting the pavement. This is useful when going around corners with curbs and maneuvering around small cars in crowded parking lots.
In the top mirror on the left, you can see the side mirror of the truck beside me. You can also see it in the convex mirror. Where is it really? Goes back to that old "Perspective" thing. It is really about half way between the two views.
Between the two mirrors and the two on the other side, it is possible to slide a 70' of truck into a parking space that is often JUST wide enough. They rarely give you too much room.
When we started Truck Driving School, I could not back a truck and trailer. We practiced on an empty army base with regular width streets. I couldn't keep it on the pavement for nothing. I wobbled and wiggled that thing all over the place while frantically spinning the steering wheel in one direction and then another. I'm sure it was quite a show for the instructors. One guy was even worse than I was and he got thrown out. I truly thought that backing would be my demise in trucking.
On Friday, the instructors said that we would have a pass/fail test on Monday - we would have to back the rig up in a straight line for 100'. Sometime over the weekend, it was like a penny dropped into a gumball machine and I got the prize. Without even practicing, I knew how to do it.
Now, I can back a trailer in a straight line, curvy line, around a corner (had to do that one night in Idaho when I made a wrong turn!) or pretty much wherever you need me to.
I still have trouble backing our Taurus into a parking space though.