What does 'story by' mean?

I'm not quite sure what you mean by 'others mean story'. It's a bit unclear. Maybe you could explain it a bit more?

The novel's side story usually refers to a supplementary content created by the author after the completion of the main text. It is usually an independent story that is not directly related to the main text. There were two types of extras: one was a continuation of the original story, and the other was an expansion or adaptation of the original story. In the novel, the readers would be given a new perspective, plot, and characters, allowing them to understand the background and details of the story more deeply. Outsiders could also appear in comics, movies, television dramas, or other media as a derivative work of a novel. Outsiders were often seen as a kind of "sequels" or "derivative works" that could increase readers 'loyalty and interest in the novel. However, it should be noted that the quality of some novels may not be high, and may even contradict or conflict with the main body of the novel, so readers need to choose carefully.

Well, 'story' usually refers to a narrative or an account of events, either real or fictional.

It's hard to say exactly. 'A story is a' could be interpreted in various ways. Maybe it's emphasizing that a story is a form of expression, a means of communication, or a creative construct.

Hard to say exactly. '20' might represent a score, a level, or even a page number. It really depends on the context and details of the story.

A 1.5 story structure means that the upper part of the building is sort of in-between a full story and a half story. It could have limited space or be used for specific purposes like storage or a loft area.

It could refer to a building that has five floors or levels. For example, 'a 5-story building'.

In most cases, 'story' means a sequence of events that are told or written to entertain, inform, or convey a message. It can be fictional or based on real life. For example, a story can be a fairy tale or a personal memoir.

The story of 'Mean Girls' is basically about high school social dynamics and the drama that ensues when a new student tries to fit in and deal with the popular but mean girls.

It could refer to a kid in the story 'A Christmas Story' who behaves in a mean way.