Dragonflight is a novel of Pern by Anne McCaffrey - the first of the series to be written. Originally published in 1968, Dragonflight set up one of the most well known worlds in science fiction and fantasy.
The world Pern is one that is haunted by the Red Star -another planet swinging about the sun on a highly elliptical orbit. Every 200 years or so, Thread spews from this planet and attacks all organic matter, rapidly eating it away. Few things destroy Thread - cold, fire, acid and water.
To combat Thread, there are dragons - honest to goodness fire breathing dragons. Not only can dragons fly, but they can teleport through between - a brief and cold nothingness (also a quick escape from Thread that might have attacked a dragon). Bonded for life with a dragon are Dragonriders - humans who have Impressed the dragon at birth and form a telepathic link.
It has been 400 years since the last Threadfall and only Benden Weyr (caves where dragons and their riders live) remains occupied. The old queen dragon is dying and a rider for the new one needs to be found. At Ruatha Hold (stone fortress carved in the side of a hill or mountain - impervious to thread), Lessa, heir to the lord holdership but forced to work as a servant by an usurper lives and plots to retake what is rightfully hers until she is selected as a candidate to be the rider of the new queen.
This book brings back fond memories of old - my mother reading to us on the couch. Over the years, she read all 6 of the two trilogies to the rapt ears of me and my siblings. My parents also enjoyed the series and it turns out if I had been born a year later, my name would have been Jaxom (she didn't start reading the series until 1974).
Since the writing of this book, McCaffrey has returned to Pern many times. In the later cases the books are not well formed trilogies as were the first sets. Furthermore, these books often interweave with the same time frame from different points of view. Most obviously, The White Dragon, Dragondrums and The Renegades of Pern all happen at the same time... or timeish - they overlap.
Dragonriders of Pern
Harper Hall
Historical
White Dragon timeframe and later
ISBN 0345335465
Awarded a Hugo Award in 1968 for the novella Weyr Search and Nebula Award for novella Dragonriders in 1969. These two novellas were later incorporated into Dragonflight.