A logical fallacy is just a statement that is not logically correct, or drawing a conclusion from an argument that does not logically follow. It can apply to formal or informal logic. A formal logic example is something like this: If an animal is a dog, then it has four legs. My cat has four legs. Therefore, my cat is a dog. That's obviously incorrect, as cats cannot be dogs. Much more common in every day life are informal logical fallacies. There are far too many to list, but a common one that most people are familiar with is the straw man, where a person intentionally misrepresents someone else's position in order to attack the false position and not the real one. An example of this would be: Bob: "I like having a pet dog". Alice: "Why do you hate cats?" Here, Bob never said anything about cats, but Alice drew out that false inference in order to attack Bob. Answer from internetboyfriend666 on reddit.com