Interactive gradient descent demo: a dot on a U-shaped loss curve for one weight, with a tangent line, step preview, adjustable learning rate, and readouts of weight, slope and loss; plus a strip showing every weight receiving its own nudge simultaneously.

One weight's slice of the loss landscape
Gradient descent on one weight loss this weight's value
Weight: 4.40Slope: 2.40Loss: 3.28Steps: 0
Press the button: the weight moves against the slope. Green line = local slope, arrow = next step.
update rule: new w = w − learning rate × slope
Same moment, every weight
All weights nudged at once
One backward pass prices every weight's nudge; all five billion move in the same instant, each by its own slope.