Not a Down Pin. You "pull" that pin away, you will have the pin come back on it's base. Probably the most common "call" people make on leaning pins.

Down Pin. You can clearly see it is down. If the machine gives a count of 13 as an example, it would have to be changed into a Strike.

Down Pin. This is where you can commonly see the string get snagged my the pinsetter and it not being released. If this happens, the Judge of Play, or whomever is making the call, should correct the score accordingly.

Not a Down Pin. This is common if the base is worn, or the "pin pucks" are grooved in and are concave after lots of use. It is more common on wood lanes for the pin pucks, but the base is a common occurrence for it all. With the old rule, it is technically leaning, after throwing a 13 count as an example, a pin barely bumps into the corner, it could lean a little more, and someone could call it. Much tougher with the black bases as well, when it is 60 feet out.