Concepts
The principles behind the movements of Brazilian Jiu-Jitsu. Techniques are what the art does; concepts are why it does them the way it does.
What shapes the shape
Each concept is a catalogue row on this art. Facet tags appear only when they are stored on the entry.
Base and Posture
Maintaining a stable center of gravity and an upright, structurally sound spine/frame in every position — the physical precondition for both offense (preventing sweeps and reversals) and defense (preventing the opponent's submission attempts).
Guard Retention
The skill of preventing a top-position opponent from passing to side control, north-south, mount, or back control — maintaining at least one leg between tori and the opponent's hips (the IBJJF's own structural definition of "guard").
Framing
Using the forearms, knees, or shins as rigid structural braces against an opponent's hips, shoulders, or head to create and maintain distance, preventing them from consolidating a dominant position — the mechanical basis underlying most of the escapes coded in this corpus (bjj-mount-escape-hip, bjj-back-escape, bjj-side-control-escape, bjj-half-guard-escape).