A reinforcement is used to resist the shear and diagonal tension stresses in a concrete structural member. The term stirrups usually refers to lateral reinforcement in flexural members and the term ties to lateral reinforcement in vertical compression members. Also,  a curved “U” shaped or box shape steel bar and arranged perpendicular to is defined as stirrup. Or, at an angle to the longitudinal reinforcement, and perfectly anchored.
The video will show it and explain it visually better.

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