A mass market paperback in OK condition; slightly yellowed pages, worn cover. This is a new edition published in 1991 ("Author's Definitive Edition" label on the cover); the original copyright is 1977. From the back: 
 "Card has taken the venerable sf concepts of a superman and interstellar war against aliens, and, with superb characterization, pacing and language, combined them into a seamless story of compelling power. This is Card at the height of his very considerable power--a major SF novel by any reasonable standards." --Booklist 
 My review: 
 I picked this book up through FreeCycle because I loved Card's books on writing, and I knew the book by reputation as an SF classic and award-winner (both Hugo and Nebula.) Then it sat on my shelf for three years. My interests were more with history and HF, so it languished. This year I started a new system for reading my TBR pile which didn't allow me to overlook older books (I'm reading by size-large books for home and small books for commuting and have given myself permission to stop reading, if something doesn't grab me.) This book got promoted from commuting book to fireside book because it grabbed me. It deserved its awards and has completely held up over the decades. 
 The titular Ender is a super smart child--a boy of six--at the beginning of the book, who is recruited by the international space force, to prepare to command a fleet to defend against an invasion by "the buggers"; an alien race who tried to invade and colonize Earth several decades before and were barely repulsed. The book is from Ender's point of view, except brief adult conversations that lead off each chapter that give some context and foreshadow action. The book is cleverly written, the characters well-drawn, the plot compelling, and the ending delivers. Highly recommended!