Disk

Disk[{x,y},r] represents a disk of radius r centered at {x,y}.

Disk[{x,y}] gives a disk of radius 1. 

Disk[{x,y},{rx,ry}] gives an axis-aligned elliptical disk with semiaxes lengths rx and ry.

Disk[{x,y},…,{θ1,θ2}] gives a sector of a disk from angle θ1 to θ2.

Disk[{{x1,y1},{x2,y2},…},…] gives multiple identical disks centered at the given coordinates.

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