When an author decides to write about the real present, these books over time become testimonials. Bear in mind that the real present is difficult to write. Details must be exact. Some examples of novels written in the real present are by authors like Daniel De Foe, Jane Austen and Charles Dickens. A modern example is Jacqueline Susann who depicted the1960's rich and famous in her notorious novel 'Valley of the Dolls.' This book describes in detail the drugs, sex, drinking, backstabbing and scandals that permeated the entertainment industry of that era.
Stories told in the future must relate to the present in order to have mass market appeal. Science fiction which does not analyse and soothe a fear about the future will not appeal to a mainstream audience. It will only attract a SF audience. Michael Crichton's 'Jurassic Park' became a bestseller because it raised to gigantic proportions two profound, global fears - the ethics of genetic engineering and mass tourism.
The recent past is a popular setting with readers. Catherine Cookson's late Victorian and post World War I dramas have widespread allure. The eras depicted in her novels are recent enough for readers to relate to, and the conflicts they raise are contemporary enough for readers to care. So it is too with Stephen Kyle's "The Experiment," which begins at the end of the Nazi regime, though most of the action takes place in the 1970's. These types of stories serve to question history and sometimes even allow the author to reinvent it. Were Nazi scientists able to manipulate genes, even to creating genetic memory as is the premise of 'The Experiment?' Because history is a matter of interpretation, the author's version of it may become vastly popular depending on where public opinion lies at the time the book is released.