The dark side of the force is often the exact opposite of the light. Many consider this to be the “evil” side of the force, but some believe that is an unfair concept. In fact, it is this very ideology that caused many Jedi to turn from the light to the dark side. Jedi were criticized because they refused to let trainees or padawans learn or be exposed to dark side use. Which made them more sensitive to accepting it later on. The dark side uses emotion entirely, as a dark force user will focus their entire workings of the force based on their emotion at the time. If angry, they could cause the deaths of thousands.
[Image via StarWars.com]Their use is also unnatural compared to the light side, so they are able to achieve feats that are simply impossible to explain scientifically. Such as bringing down an entire Star Destroyer. The issue is that too much exposure and use of the dark side will consume the user. It will take over an individual’s character and consume their soul. This was a total opposite from the light because you sacrifice yourself as a light user while you become selfish and all-consuming as a dark user. “The Living Force” is the energy of all life, and using dark side concepts will mess with the Cosmic Force, causing total eradication of the self.