Yes, I'm new to Logging

Hello. I am new to combat logging and am confused as to how I can use it to help improve. Would someone direct me to information regarding what exactly parsing is and how it is used to compare my log with others? For example, if I look at this fight and compare myself (luchea) to the other shaman, I can’t for the life of me figure out why the other shaman is so much better. I mean, there appears to be only one ability that is different between us (Ancestral Guidance).

I guess what I’m asking is how do I use this information to improve and be as good as the other shaman?