What makes a book or a short story science fiction?

when a book includes facts but is portrayed with fiction characters and fantasy's.

Explanation:

Science fiction, also referred to as "sci-fi," is a genre of fantasy literature whose material is imaginative, but focused on science. It relies heavily on scientific facts, theories, and principles as support for its settings, characters, themes, and plots, which make it different from fantasy.

Shown below;

Explanation:

When it talks about experiences which is a bit exaggerated and not practicable in our physical world. Especially when these experiences relates with man's venture into some new kind of interaction with. Like men flying; interacting with so called aliens who have invaded the earth. The order of this writing relates to scientific theories which is not yet practicable in the real world but seen as the reality for developing its main ideas and characters.

c. "but thy eternal summer shall not fade" (line 9)