The Dragon Riders of Pern by Anne McCaffrey

The colonists of the planet Pern fight for survival against Thread, an invasive, deadly organism from space that falls from the sky and consumes all organic matter it touches.

To survive, the human colonists genetically engineered native, flying, fire-breathing creatures into massive rideable dragons. They form lifelong, telepathic bonds with their riders, and together they scorch the deadly Thread from the skies.

The Dragonriders of Pern is a classic science fantasy series by Anne McCaffrey that blends medieval feudal societies with advanced sci-fi concepts.