A question about turning to the dark side...
When someone embraces the dark side, it's obvious that they give in to their own anger, but does the force fill them with anger purely created by the force? or is it just their own?
So when Anakin fell, did anger that was not even his fill him? Is it essential to give in to your anger to use the dark side? Is that the only way?
It is their own anger, and they dwell on it.
And usually, yes, anger is the most common path to the Dark Side, seeing as other emotions that can be used to empower a Dark Sider usually lead to anger.
However, anger isn't the only emotion. Fear, Jealousy, Hubris, Anger, Hatred...
In Anakin's case, he fell to the Dark Side because of Fear, then Anger and Hatred came from that, directed at Obi-Wan.