The Johari Window and the DiSC Model
Joseph Luft & Harry Ingham (Johari); William Marston (DiSC) · 1955
"Self-awareness and team dynamics can both be mapped with simple two-axis models — the Johari Window splits what's known/unknown to self versus others, while DiSC categorizes behavioral style along dominance and sociability — giving structured vocabulary to traits that otherwise stay vague."
There are things about you that you know and others don't, and things about you that others see and you don't. The Johari Window is just a grid that makes that asymmetry visible.
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The Feynman Technique and the Leitner System
"Genuine understanding is tested by whether you can explain a concept simply enough for a child, and genuine retention is engineered by spacing review intervals according to how well you already know the material — two separate mechanisms that most study habits conflate into one vague 'studying' activity."