Fallacy

According to most dictionaries, fallacy is defined as mistakes in belief based on unsound argument.

There are several ways that fallacy can creep into arguments:

Ignorance: This is where someone takes advantage of another's lack of knowledge, thereby convincing them with false information.

You can't prove that aliens didn't help the Egyptians to build the pyramids, so therefore I believe they did.

Popular Opinion: This is common. People use popular opinion, which is often incorrect, to force an argument.

Lots of people love that song, so it must be good.

Authority: When haven't we experienced this. It's the argument from what is considered modesty. Basically, the person using this in an argument sites authority as proof, asking:
Do you know more than they do.

Association: This is where someone sites guilt by association. You must be guilty if you associate with them.

He must be insane because he doesn't believe in God.

Personal Attack: I'm sure you know this idea. It's what politicians do. They attack their opponent by insulting them.

Begging the Question: This is where the question is phrased with a conclusion to the argument.

If they didn't steal my apple, who did?

Circular Argument: The argument takes its proof from within the argument, not from outside sources.

I believe that Pepsi is great because the bottle says so.

Correlation: This is where the presenter connects two sequential events, implying that one caused the other.

I stepped on a crack in the walk and lost my wallet. Therefore my stepping on the crack caused bad luck.

Dilemma: Also know as bifurcation. The argument is presented with only two options.

If you don't vote for my candidate, you're an idiot.

Non Sequitur: This is where the conclusion doesn't follow from the prepositions.

Humans are mammals.
Joe is a mammal.
Therefore, Joe is a human.

Slippery Slope: This is where an argument claims that a small action will lead to more severe or extreme result.

If you allow gay people to marry, next people will want to marry a dog.

No offence intended by any of these. It's just me trying to explain the obvious.

Thanks for reading.