> ## Documentation Index
> Fetch the complete documentation index at: https://docs.wandb.ai/llms.txt
> Use this file to discover all available pages before exploring further.

> Track machine learning experiments with W&B to log metrics, hyperparameters, system metrics, and model artifacts.

# Experiments overview

export const TryProductLink = ({url}) => <a href={url} target="_blank" rel="noopener noreferrer" className="github-source-link">
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      <circle cx="12" cy="10" r="2"></circle>
      <circle cx="20" cy="14" r="2"></circle>
    </svg>
    Try in W&amp;B
  </a>;

export const ColabLink = ({url}) => <a href={url} target="_blank" rel="noopener noreferrer" className="colab-link">
    <svg width="20" height="20" viewBox="0 0 24 24" fill="currentColor" xmlns="http://www.w3.org/2000/svg">
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    Try in Colab
  </a>;

<CardGroup cols={4}>
  <ColabLink url="https://colab.research.google.com/github/wandb/examples/blob/master/colabs/intro/Intro_to_Weights_%26_Biases.ipynb" />

  <TryProductLink url="https://wandb.ai/stacey/deep-drive/workspace?workspace=user-lavanyashukla" />
</CardGroup>

Track machine learning experiments with a few lines of code. You can then review the results in an [interactive dashboard](/models/track/workspaces/) or export your data to Python for programmatic access using our [Public API](/models/ref/python/public-api/).

Utilize W\&B Integrations if you use popular frameworks such as [Keras](/models/integrations/keras). See [W\&B Integrations](/models/integrations) for a full list of integrations and information on how to add W\&B to your code.

<Frame>
  <img src="https://mintcdn.com/wb-21fd5541/88iR80mZ8tuFCZUU/images/experiments/experiments_landing_page.png?fit=max&auto=format&n=88iR80mZ8tuFCZUU&q=85&s=3250a01d7dd14400455474aee6818e30" alt="Experiments dashboard" width="4354" height="2978" data-path="images/experiments/experiments_landing_page.png" />
</Frame>

The image above shows an example dashboard where you can view and compare metrics across multiple [runs](/models/runs/).

## How it works

Track a machine learning experiment with a few lines of code:

1. Create a [W\&B Run](/models/runs/).
2. Store a dictionary of hyperparameters, such as learning rate or model type, into your configuration ([`wandb.Run.config`](/models/track/config/)).
3. Log metrics ([`wandb.Run.log()`](/models/track/log/)) over time in a training loop, such as accuracy and loss.
4. Save outputs of a run, like the model weights or a table of predictions.

The following code demonstrates a common W\&B experiment tracking workflow:

```python theme={null}
# Start a run.
#
# When this block exits, it waits for logged data to finish uploading.
# If an exception is raised, the run is marked failed.
with wandb.init(entity="", project="my-project-name") as run:
  # Save mode inputs and hyperparameters.
  run.config.learning_rate = 0.01

  # Run your experiment code.
  for epoch in range(num_epochs):
    # Do some training...

    # Log metrics over time to visualize model performance.
    run.log({"loss": loss})

  # Upload model outputs as artifacts.
  run.log_artifact(model)
```

## Get started

Depending on your use case, explore the following resources to get started with W\&B Experiments:

* Read the [W\&B Quickstart](/models/quickstart/) for a step-by-step outline of the W\&B Python SDK commands you could use to create, track, and use a dataset artifact.
* Explore this chapter to learn how to:
  * Create an experiment
  * Configure experiments
  * Log data from experiments
  * View results from experiments
* Explore the [W\&B Python Library](/models/ref/python/) within the [W\&B API Reference Guide](/models/ref/python/).

## Best practices and tips

For best practices and tips for experiments and logging, see [Best Practices: Experiments and Logging](https://wandb.ai/wandb/pytorch-lightning-e2e/reports/W-B-Best-Practices-Guide--VmlldzozNTU1ODY1#w\&b-experiments-and-logging).
