Re: No Moon
Planets have different sorts of moons. Ours is believed to have been the result of a collision, the remains of which can be seen in the night sky. Other planets might capture their moons, either as dust and rock that forms into a moon by accretion, or as asteroids that are sucked into a stable orbit.
So, you might have no moon, but you might still see small asteroids reflecting light, or a shiny, or dark, ring of accretion material that might one day in the planet's future be a moon. Your inhabitants might have no knowledge of what it was, but they would probably notice it.
As far as world building on the planet's surface, the absence of the moon would probably contribute to highly chaotic weather systems. No tides would affect the oceanic currents which vary sea temperatures. Combined with the planetary spin producing a faster jet stream, this could result in some spectacular storms.