Facts v. Opinions

A fact is a piece of information that is true and can be proved.

• A Ferrari is faster than a Prius.
• Dogs are canines.
• The sun is a ball of flaming gas floating in space.

An opinion is a personal belief; opinions are not facts, they are feelings.

• I think a Ferrari is a better car than a Prius.
• In my opinion, dogs make best pets.
• I believe the sun is beautiful.

An opinion generally can't be "wrong" because it is what a person believes and/or feels, not necessarily what is factually true. 

People can disagree about whether or not an opinion is logical. 

When reading nonfiction, you should always ask yourself whether you are reading facts or opinions, because it is possible to write an opinion so that it looks like a fact.

• A Ferrari is a better car than a Prius.
• Dogs make the best pets.
• The sun is beautiful.