# backpropagation

CEFR C1 · Noun

Source: https://englishreference.com/word/backpropagation
Updated: 2026-09-28

## Definition

the algorithm a neural network uses to calculate its mistakes and figure out how to adjust its internal weights.

For teachers: an efficient algorithm that applies the mathematical chain rule backwards through computational graphs to compute gradients of the loss with respect to all parameters.

## Examples

- During training, backpropagation tells the network how to correct its errors on each picture.
- The breakthrough in deep learning occurred when backpropagation was successfully scaled on graphics processing units.
- Vanishing and exploding gradients during backpropagation through deep architectures necessitated the introduction of residual skip connections and layer normalization.

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