The beginShape() function begins recording vertices for a shape and endShape() stops recording. A vertex is a location in space specified by X, Y, and sometimes Z coordinates. After calling the beginShape() function, a series of vertex() functions must follow. To stop drawing the shape, call the endShape() functions.
Original Processing.org Example: Vertices
// All Examples Written by Casey Reas and Ben Fry // unless otherwise stated. size(200, 200); background(0); noFill(); stroke(102); beginShape(); curveVertex(168, 182); curveVertex(168, 182); curveVertex(136, 38); curveVertex(42, 34); curveVertex(64, 200); curveVertex(64, 200); endShape(); stroke(51); beginShape(LINES); vertex(60, 40); vertex(160, 10); vertex(170, 150); vertex(60, 150); endShape(); stroke(126); beginShape(); vertex(60, 40); bezierVertex(160, 10, 170, 150, 60, 150); endShape(); stroke(255); beginShape(POINTS); vertex(60, 40); vertex(160, 10); vertex(170, 150); vertex(60, 150); endShape();