1. Never make these
Debate Mistakes I

2. ad hominem Latin for “towards the man”
more colloquially, “a personal attack!”
in the vernacular, “You’re a doody-head!”
Think of this as “We want a pitcher not a belly itcher”

3. ad hominem - Example
William Bennett…, leader… of the antirap campaign…, [has] had no trouble finding antipolice and antiwomen lyrics to quote in support of [his] claim that "nothing less is at stake than civilization" if rappers are not rendered silent. So odious are the lyrics, that rarely do politicians or journalists stop to ask what qualifies Bennett to lead a moralistic crusade on behalf of America's minority youth. Not only has he opposed funding for the nation's leader in quality children's programming (the Public Broadcasting Corporation), he has urged that "illegitimate" babies be taken from their mothers and put in orphanages.
Source: Barry Glassner, The Culture of Fear (1999), p. 122.

4. ad hominem - Analysis
A debater commits the Ad Hominem Fallacy when he introduces irrelevant personal attacks about his opponent. Such red herrings may successfully distract the opponent or the audience from the topic of the debate.
Ad Hominem is the most familiar of informal fallacies, and—with the possible exception of Undistributed Middle—the most familiar logical fallacy of them all. It is also one of the most used and abused of fallacies, and both justified and unjustified accusations of Ad Hominem abound in any debate. It is a frequently misidentified fallacy, for many people seem to think that any personal criticism, attack, or insult counts as an ad hominem fallacy.

5. tu quoque Latin for “you, also”
more colloquially, “you too!”
in the vernacular, “I know you are but what am I!”
Think of this as “Two Wrongs Make a Right”

6. tu quoque - Example
Q: Now, the United States government says that you are still funding military training camps here in Afghanistan for militant, Islamic fighters and that you're a sponsor of international terrorism.… Are these accusations true? …
Osama Bin Laden: …At the time that they condemn any Muslim who calls for his right, they receive the highest top official of the Irish Republican Army at the White House as a political leader, while woe, all woe is the Muslims if they cry out for their rights. Wherever we look, we find the US as the leader of terrorism and crime in the world. The US does not consider it a terrorist act to throw atomic bombs at nations thousands of miles away, when it would not be possible for those bombs to hit military troops only. These bombs were rather thrown at entire nations, including women, children and elderly people and up to this day the traces of those bombs remain in Japan. The US does not consider it terrorism when hundreds of thousands of our sons and brothers in Iraq died for lack of food or medicine. So, there is no base for what the US says and this saying does not affect us.…
Source: "CNN March 1997 Interview with Osama bin Laden" (PDF)

7. tu quoque - Analysis
tu quoque is a very common fallacy in which one attempts to defend oneself or another from criticism by turning the critique back against the accuser. This is a classic Red Herring since whether the accuser is guilty of the same, or a similar, wrong is irrelevant to the truth of the original charge.
However, as a diversionary tactic, tu quoque can be very effective, since the accuser is put on the defensive, and frequently feels compelled to defend against the accusation.
Source: S. Morris Engel, With Good Reason: An Introduction to Informal Fallacies (Fifth Edition) (St. Martin's, 1994), pp