It can be difficult and confusing to distinguish between fact, opinion, and bias. Writers will often wrap facts up amongst opinions that make it hard to pull out the truth. To help differentiate, it is important to be able to define each one.
Fact: A fact is something that is an objective proof. It can be shown to be true through evidence.
Opinion: An opinion is something that cannot be proven. IT typically is based on emotion, and contains very descriptive language such as large, best, worst, greatest, etc.It also tends to have an exaggerated effect to it.
Bias: A bias is prejudice in favor of or against one thing, person, or group compared with another, usually in a way considered to be unfair.