Half-elves and Half-orcs

Elves, orcs, and humans are interfertile, so the result is half-orcs and half-elves from byblows. as usually defined, were humanoids born through the union of an elf and a human. Whether a half-elf was raised by their human parent or their elven parent, they often felt isolated and alone. Because they took around twenty years to reach adulthood, they matured quickly when raised by elves (who think they look like humans), making them feel like an outsider in either place. Same with half-orcs, as they are usually born from human/orc pairings. However, it is known that orc and elf pairings will also produce half-orcs and half-elves.

Half-Elves
The half-elven race began (and still continues to a small degree) as the product of relationships between humans and elves, but has developed into a true-breeding race. Half-elves combine human and elven traits, and as a consequence tend to be considered outsiders by both races. On the other hand, the combination of human skill with elven beauty makes them good artists and entertainers as well as well-traveled adventurers.

Half-Orcs
Half-orcs are result of orcs mating with other humanoid races. Several orc tribes actively work toward breeding half-orc children for their greater mental capabilities. These half-breeds are despised by most of the world, however, which sees them as the spawn of violence or a filthy perversion. However, pairings between orcs and humans (or elves) can be seen as beneficial too the partners.