What is the Definition of Bias?

Bias is being favorable to something because you have a special interest in it. For example, if someone asks you where is the best place to get a hamburger? You’re going to recommend ‘burger joint’ because you work there. So because you work there you have bias. Or you may tell them to go somewhere else, because you really dont’ like working at ‘burger joint’. Bias can work either way, if you cannot provide a fair and impartial opinion.