gradient descent
The update rule w \leftarrow w - \eta L'(w) (or its gradient version for several parameters): repeatedly move every parameter a small distance against its own slope, so the loss keeps falling.
Examples
On L(w)=(w-3)^2 from w_0=0 with \eta=0.1: w moves 0, 0.6, 1.08, 1.464, \ldots, toward the minimum at w=3.
See also
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