OBJECTIVITY & SUBJECTIVITY
The difference between these two important ideas is the difference between fact and opinion. Facts are objective and provably true; however, if no clear facts exist about a topic, then a series of balanced opinions needs to be produced to allow the reader to make up his or her mind; opinions are subjective ideas held by individuals and so are always biased. If unbalanced opinions are presented as if they are facts, they act as propaganda or persuasion, e.g. a newspaper headline might state: "Youngsters are the prime cause of trouble in this area". This is presented as an objective fact but is clearly a subjective opinion.
An objective piece of information, therefore, needs either to be the whole truth and at least be unbiased or balanced, whereas a subjective point of view is biased because it is either not the complete picture or it is merely a viewpoint or expression of feelings.
When studying literature, it is best to be objective when you consider a text's qualities. Of course, literature read for pleasure should be approached subjectively as this allows you to 'be there' with the characters, feeling involved with the plot and so forth. But when you discuss literature for an essay, it is far safer to 'stand back' and see it objectively for what it is: no more than an attempt to engage and hold your attention, build trust in its writer, and persuade you to a way of thinking - the writer's way!
Looked at objectively, a text is no more than a 'vehicle' for communicating a persuasive message. This applies to characters and settings, too - all highly compelling and believable 'vehicles' for the writer to convince you to think his or her way!