Russian Ordinals refers to the numbering system used to denote position, or 'order'. In other words:
First... Second... Third...
The most common use for this system is days of the month, and it is also the system used to denote order of start and finish. You will notice a common pattern for most of the ordinals that is based on the Russian cardinals (the regular counting system of "One, two, three...").
Refer to the cardinals first, and then compare them against the numbers below to see these patterns occurring.