1910 Penny, Error Or Normal Coin?

The error is called a Rotated Die. Dies are set in the coin press to align the correct way (depending on the country of manufacture) but with repeated pounding from coin striking whatever it is that holds the die (usually the non-hammer die, as if the hammer die were to turn it could fall out) in place can come slightly loose and turn. The larger the degree of rotation the more valuable the coin. I'm sure some others will chime in with some further explaining.

Not an expert based on other examples of this type with severe die rotation but die rotation does not add very much to the value unless 180* (severe). A coin like this with medal turn and not coin turn (~180*) would have a premium - but again not that much ...

This in general is called the "coin alignment". If you hold a coin by the edges between your pointing finger and the thumb the easiest way to turn it to the other side (without involving any other body parts) is to flip it upside down by twisting your fingers.

When both sides are up the same way it is called the "medal alignment", because if a medal hangs on someone's chest usually people turn it around the vertical axis through the point of suspension.

Some countries favor one alignment for their coins, other favor the other, some countries have done both. As for the minting process, the alignment doesn't really matter; but it is something they have to watch for if they want to be consistent.