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  "body": "\n## Summary\n\nA cobweb plot is a picture of an orbit of a map of the real line.\nIt is drawn on top of the graph of the map and the diagonal $y = x$.\nThe orbit is traced by a path that goes alternately vertically to the graph and horizontally to the diagonal.\nIt shows at a glance whether an orbit converges to a [[fixed point|R6QVS6P21N]], cycles around a [[periodic point|T75CZ5H47N]], or wanders.\nCobweb plots are a standard first tool for maps of an interval such as the logistic map.\n\n## Explanations\n\n### L1 human\n\nDraw the graph of the map $f$ and the line $y = x$ in the same picture.\nStart at a value $x_0$ on the line, and go up or down to the graph to read off $f(x_0)$.\nThen go sideways to the line to make $f(x_0)$ the new starting value.\nRepeating these two moves draws a staircase or a spiral.\nFor $f(x) = \\cos x$, the path spirals in to the point where the graph of $\\cos$ crosses the diagonal, near $0.739$.\nA staircase means the orbit approaches the fixed point from one side, and a spiral means it jumps from side to side.\n",
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