Hard science fiction

Hard Science Fiction is a catagory Science Fiction which while set in the future, obeys the laws and priniciples of science, or at the very least does not routinely and blatently violate them. For various thematic purposes (Such as being able to cross even short Intersteller Distances in a timespan shorter than Decades via FTL drives) most science fiction is not completly Hard, although certain peices of Science Fiction are harder than others in making less errors such as having spacecraft move and manuver using Neutonian Physics instead of a manner as they would inside an atmosphere.