# What is Epoch? Definition & Technical Mechanics

> **Source:** [SPIDITS AI AI Glossary](https://spidits.com/ai-glossary)  
> **Category:** Model Training  
> **Canonical Citation:** [https://spidits.com/ai-glossary/epoch](https://spidits.com/ai-glossary/epoch)

## Definition
An Epoch is a single complete pass of the entire training dataset through a machine learning model. Training typically consists of many epochs to allow the network to refine weights and biases based on multiple passes over the data.

## Architectural Mechanics & Deep Dive
An epoch is a training term that represents one complete pass of the entire training dataset through the neural network. During a single epoch, the model processes all training examples in batches, updating internal weights via backpropagation. Training deep learning models typically requires multiple epochs, balancing learning progression against the risk of overfitting the training set.

## Industry Applications & Real-World Use Cases
Model training progress tracking, loss plotting, and optimization cycles

## Frequently Asked Questions

### How does an epoch differ from a batch?
A batch is a small subset of the training data. An epoch is completed only when all batches in the dataset have passed through the network.

### Can too many epochs be harmful?
Yes, running too many epochs can lead to overfitting, where the model memorizes the training data.

## Related Terminology
- [overfitting](https://spidits.com/ai-glossary/overfitting)
- [supervised-learning](https://spidits.com/ai-glossary/supervised-learning)

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*From the SPIDITS AI Knowledge Base (336+ terms indexed). Explore full technical definitions: [https://spidits.com/ai-glossary](https://spidits.com/ai-glossary)*