BOLL is my favorite TA tool. I am gonna show my reasons. However, I am still a newbie, and this is something I learned just a couple of days ago. So, correct me if I was wrong.
Generally speaking, the first time I learned BOLL, I was confused by its literal definition online. However, thanks to some vivid descriptions in moo's community, I think I grasped the basic understanding.
Adding the link now. These might be really helpful if you are still not clear about BOLL
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