Definition: An invented prose narrative shorter than a novel usually dealing with a few characters and aiming at unity of effect and often concentrating on the creation of mood rather than plot.
Length: There is no set length for a short story, and the word count can vary greatly, ranging anywhere from 1,000 to 20,000 words. In flash fiction, stories are even shorter, ranging from as few as 100 words up to 2,000 words.
Elements:
The main difference between longer fiction and the short story is every word has to count and move the story forward. There simply isn't room for "fluff" or filler.
Elements of Fiction Writing - Characters and Viewpoint by 
Crafting Novels and Short Stories by Learn How to Create Stories That Captivate Agents, Editors, and Readers Alike! Inside you'll find the tools you need to build strong characters, keep your plots moving, master the art of dialogue, choose the right point of view, and more. This comprehensive book on the art of novel and short story writing is packed with advice and instruction from best-selling authors and writing experts like Nancy Kress, Elizabeth Sims, Hallie Ephron, N.M. Kelby, Heather Sellers, and Donald Maass, plus a foreword by James Scott Bell. You'll learn invaluable skills for mastering every area of the craft: Define and refine your characters. Make your plot and conflict high-energy and intense. Hone your story's point of view. Create a rich setting and backstory. Craft dialogue that rings true. Select the right words and descriptions throughout your story. Revise your story to perfection. Throughout you'll find supplemental sections that cover special topics like getting started, beating writer's block, researching your work, and getting published. They'll help you integrate your skills into a balanced, productive, and fulfilling career. Whether you're writing flash fiction, a short story, a novel, or an epic trilogy, you'll come away with the tools you need for strong and effective storytelling.
Short Story Theories by "Short Story Theories: A Twenty-First-Century Perspective" problematizes different aspects of the renewal and development of the short story. The aim of this collection is to explore the most recent theoretical issues raised by the short story as a genre and to offer theoretical and practical perspectives on the form. Centering as it does on specific authors and on the wider implications of short story poetics, this collection presents a new series of essays that both reinterpret canonical writers of the genre and advance new critical insights on the most recent trends and contemporary authors. Theorizations about genre reflect on different aspects of the short story from a multiplicity of perspectives and take the form of historical and aesthetic considerations, gender-centered accounts, and examinations that attend to reader-response theory, cognitive patterns, sociolinguistics, discourse analysis, postcolonial studies, postmodern techniques, and contemporary uses of minimalist forms. Looking ahead, this collection traces the evolution of the short story from Chaucer through the Romantic writings of Poe to the postmodern developments and into the twenty-first century. This volume will prove of interest to scholars and graduate students working in the fields of the short story and of literature in general. In addition, the readability and analytical transparence of these essays make them accessible to a more general readership interested in fiction.
The Art of the Short Story by 52 Great authors, their best fiction and their insight into writing.
The Complete Stories by Taken together, these stories reveal a lively, penetrating talent that has given us some of the most powerful and disturbing fiction of the twentieth century.
Long Story Short by This extraordinary collection gathers short-short stories--none longer that 1,800 words--by some of North Carolina's best contemporary writers.
The Red Convertible by These stories, spellbinding in their boldness and beauty, are a stunning literary achievement.
A Christmas Memory by All three stories are distinguished by Capote's delicate interplay of childhood sensibility and recollective vision.
The Necklace and Other Short Stories by Nine memorable classics, characterized by ironic twists of plot.
A Curtain of Green by This is the first collection of Welty’s stories, originally published in 1941. It includes such classics as “A Worn Path,” “Petrified Man,” “Why I Live at the P.O.,” and “Death of a Traveling Salesman.” The historic Introduction by Katherine Anne Porter brought Welty to the attention of the american reading public.