There are many different types of logical fallacies, all of which render the authors argument invalided. The presence of a formal fallacy in an argument does not imply anything about the argument's premises or its conclusion. Even so, speakers and writers use faulty logic and irrational emotional appeals to persuade there readers everyday, newspapers and television are great examples of this. But the cost of the risk is great, if you try to slide one by your readers and they see through your trick you will loose your credibility instantly.
One example is hasty generalization: the writer bases the argument on insufficient or unrepresentative evidence. Say that you own two dogs of the same breed and you are attacked by one of them. If you then declare that all dogs of this breed are viscous, you are making a hasty generalization. In other words if you come to this conclusion and your generalization is drawn from a sample that is too small, your conclusion is invalid.
Another example of logical fallacy is begging the question, as the writer presents the truth what is supposed to be proven by the argument. An example here could be the statement "All useless laws such as Reform Bill 13 should be repealed." The writer has already assumed that the bill is useless without assuming responsibility for proving that accusation. Then the writer may use red herring, where he will introduce an irrelevant point to divert the readers attention from the main topic. This term actually originates from an old tactic used by escaped prisoners, by dragging a smoked herring across there trail to confuse the tracking dogs. That right there was an example of red herring by stating the origin of the term I had the reader thinking about something completely different from the actual topic.
There are many other types of logical fallacies such as non sequitur, argument ad hominem, either/or, and circular thinking, but I believe that I have described the...