Okay, putting my flavour where my mouth is.
My world is a post-apocalyptic fantasy world. Basically, I mushed together as many post-apocalypse tropes with fantasy. The world was a magical place that was more Eberron than the Realms, until the world got all effed up by backstory. The globe became tidally locked, so one side always faces the sun and the other side faces away.
Elves
My elves are pretty standard, pale skinned and arrogant, being the former rulers of the known world. But their civilization is in shambles and they're dwelling in the ruins of former monuments to their glory and unable to practice the amazing magical deeds they once performed.
They're still fairly hedonistic and open culture, with public baths and no sexual hangups.
And as a quirk they tend to eat with very elaborate cutlery that's attached to their fingers for that extra level of haunty refinement.
Humans
All humans in my world are dark skinned, making them stand out from the elves. Humans with elven ancestry can be more pale skinned, as those elven traits are persistent.
Halflings
Halflings were the traders. Barge folk and sailors who were found on every river, lake, sea, and ocean, especially to the south. When the southern oceans froze they were forced onto the land and exist as hunter-gatherers on the snowy tundra. They're feral scavengers who will eat anything that can't persuade them not to.
Dwarves
Magically created by the gnomes as a slave race, dwarves were bred to be miners and artisans. And kept placated through alcohol. Dwarves continue to like drink, but view it as a tool of the oppressors and are dismissive of those who indulge.
They've claimed a deep canyon in the desert as their homeland, as that provides shelter from the sun. Mountain dwarves make their home in the walls of the canyon kingdom while hill dwarves are desert traders that travel the dunes and exchange their handiwork for supplies.
Orcs
Fitting with the post-apocalyptic aesthetic, orcs are supermutants. They're mutated by exposure dust from magical crystals that were mined to power ancient golems and magitek devices.
Half-orcs are either half-human and half-orc or simply slightly less mutated humans. Orcs aren't civilized, being short tempered and irrational. They've lost some of their self-control and sentience.
Dragonborn
I originally created my world for 4e during the build-up to that edition. I had a niche for ever race but was unprepared for WotC to add dragonmen to the game. So I stuck them on a region on the far side of the world and based their culture on Japan/ China. And then had a giant great wyrm dragon emerge and destroy their homeland Godzilla style. Because "Kaiju attack" was a type of apocalypse I hadn't done.
Goblins
These match the goblins from Pathfinder. Because they're funny and awesome.