# Test your API functionality

You can run Postman Collections to test and interact with your APIs. In Postman, a collection can be a group of saved [requests](/docs/getting-started/first-steps/sending-the-first-request/), a [workflow](/docs/collections/running-collections/building-workflows/), or a [test suite](/docs/tests-and-scripts/write-scripts/test-scripts/). When you run a collection, Postman sends some or all of the requests in the collection in the order you choose.

In Postman, you can run your collections in the following ways:

* You can [run collections manually](/docs/collections/running-collections/intro-to-collection-runs/) with the *Collection Runner*. Running collections manually is useful when you're sending a small number of requests and don't need to repeat them on a regular schedule.

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    You can also use the [Postman VS Code extension](/docs/developer/vs-code-extension/overview/) to manually run collections in the same application you use to develop your APIs.
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* You can schedule collections to run automatically. [Scheduled collection runs](/docs/collections/running-collections/scheduling-collection-runs/) are useful for automating your API testing. [Monitors](/docs/collections/running-collections/scheduling-collection-runs-monitors/) are useful for checking your API's performance, availability, and reliability.

* You can automate collection runs in your CI/CD pipeline with the [Postman CLI](/docs/postman-cli/postman-cli-overview/) or [Newman](/docs/collections/using-newman-cli/command-line-integration-with-newman/).

* You can use [webhooks](/docs/collections/running-collections/collection-webhooks/) to trigger collection runs at certain times or when a specific event happens in your application.

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  You can also run collections to simulate real-world traffic and [test the performance of your API](/docs/collections/performance-testing/testing-api-performance/) under load.
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