> ## Documentation Index > Fetch the complete documentation index at: https://confidence.spotify.com/llms.txt > Use this file to discover all available pages before exploring further. # Introduction to Experiments > Confidence is a platform for running experiments. Experiments are a way to test new ideas and measure their impact on your business. Confidence comes with multiple built-in experiment types, and you can also create your own custom experiment designs using the API.

In Confidence, experiment types define common patterns used for experimentation. Confidence supports three built-in experiment types: Experiments with one or more treatment groups, typically used in the product development phase where you test ideas. Can use both success and guardrail metrics to evaluate if new ideas are successful. A/B tests have a fixed allocation that you can't change. Experiments that rely on feature flagging from a third party. With an analysis, you can leverage the metrics and analysis capabilities of Confidence together with feature flagging from a Provider other than Confidence. You can also re-analyze experiments that you ran in the past. Experiments with only a single treatment group, where the purpose is to gradually roll out a new variant. Rollouts have an adjustable level of reach to make the experience of rolling out fully flexible. Rollouts only use guardrails. ## Related Resources Step-by-step A/B test tutorial Step-by-step rollout tutorial Learn about the statistics behind experiments