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

# Function Types

Function types determine how integration logic is implemented. Each [Action](/docs/how-membrane-works/actions) and [Flow](/reference/workspace-elements/flows) node uses a function type.

| Function Type                                                                                        | Description                                          |
| ---------------------------------------------------------------------------------------------------- | ---------------------------------------------------- |
| [JavaScript](/docs/references/functions/function-types/javascript)                                   | Run custom JavaScript/TypeScript logic               |
| [Mapping](/docs/references/functions/function-types/mapping)                                         | Transform data using declarative field mappings      |
| [REST API Mapping](/docs/references/functions/function-types/rest-api-mapping)                       | Map fields to REST API request parameters            |
| [GraphQL API Mapping](/docs/references/functions/function-types/graphql-api-mapping)                 | Map fields to GraphQL queries and mutations          |
| [API Request to External App](/docs/references/functions/function-types/api-request-to-external-app) | Make authenticated requests to a connected app's API |
| [API Request to Your App](/docs/references/functions/function-types/api-request-to-your-app)         | Make requests to your backend's Internal API         |
| [HTTP Request](/docs/references/functions/function-types/http-request)                               | Make arbitrary HTTP requests                         |
| [List Data Records](/docs/references/functions/function-types/list-data-records)                     | List records from a data collection                  |
| [Find Data Record By ID](/docs/references/functions/function-types/find-data-record-by-id)           | Find a specific record by its ID                     |
| [Search Data Record](/docs/references/functions/function-types/search-data-record)                   | Search records by query string                       |
| [Match Data Record](/docs/references/functions/function-types/match-data-record)                     | Find a record matching specific criteria             |
| [Create Data Record](/docs/references/functions/function-types/create-data-record)                   | Create a new record in a data collection             |
| [Update Data Record](/docs/references/functions/function-types/update-data-record)                   | Update an existing record                            |
| [Delete Data Record](/docs/references/functions/function-types/delete-data-record)                   | Delete a record                                      |
| [Run Action](/docs/references/functions/function-types/run-action)                                   | Execute another action                               |