As I know, F1 stands for "first generation from seed". F2 for "second generation referred to one of the plant granmother or grandad".
Pratical exemple.
A: P. rothschildianum
B: P. micranthum.
F1 is Paphiopedilum Gloria Naugle (cross between P. rothschildianum x P. micrantum), that has intermediate characteristics between the parents.
F2 is, for example, Paphiopedilum Du Motier ( cross between P. Gloria Naugle x P. vietnamense). You can see the strong influence of P. rothschildianum and the weak influence of P. micranthum in the second generation.
Backcross is A crossed with B and the result C again crosse with A or B.
so Paphiopedilum Tristar Red Dragon is a backcross of P. Gloria Naugle with P. rothschialdianum, to improve the influence of P. roth.
For division, in Italy we use D or "divisione", and it's a part of the plant, usually the awarded ones, so the division is EXACTLY the same. The original plant you divide is "motherplant".
Meristem or merclone we usually write M or "mericlone". It's used to multiplicate very fast an awarded plant in huge numbers. For example an awarded Cattleya, you make mericlone to reproduce exactly that Cattleya, but everytime the DNA multiplicates and divides (saying simple..), some mistakes can be made. So the results is not always identical to the mother plant.
That's why the differences in prices and value.
Division is the most desired: EXACTLY the same plant as awarded, so the most expensive.
Mericlone: almost as perfect as divisions, but in huge numbers (thousands..) you can have degeneration of DNA and so of the plant. Rarely the mutations give some better results. Rarely.
Seedling: with no flowers we can expect results similar to parents, better o lower ones. Good luck!
"
X self" or autoimpollination usually done with botanical species, should improve some charateristics of the plant.
In tag we use "x s" or "x self".
I like to know this stuff because when buying plants outside Italy, you know what you're buying. Well, more or less
Hope it helps