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## Resource: Introduction

## Article: Introduction

## Article Link: https://dev.wix.com/docs/api-reference/crm/members-contacts/members/member-management/custom-fields/introduction.md

## Article Content:

# About Custom Fields

Custom Fields allow you to extend member profiles beyond the default information provided by the [Wix Members Area](https://support.wix.com/en/article/site-members-about-the-members-area). With Custom Fields, you can create personalized member experiences by collecting and managing additional data specific to your business needs.

These APIs allow you to manage custom fields:

- [Custom Fields](https://dev.wix.com/docs/api-reference/crm/members-contacts/members/member-management/custom-fields/custom-fields/introduction.md): Create and manage custom fields.
- [Custom Field Applications](https://dev.wix.com/docs/api-reference/crm/members-contacts/members/member-management/custom-fields/custom-field-applications/introduction.md): Controls which custom fields apply to specific members.
- [Custom Field Suggestions API](https://dev.wix.com/docs/api-reference/crm/members-contacts/members/member-management/custom-fields/custom-field-suggestions/introduction.md): Allows you to retrieve the custom fields currently suggested on a site that haven't been assigned to members' profiles yet.

## Before You Begin

It's important to note the following before starting to code:

- A site must have the [Wix Members Area](https://www.wix.com/app-market/web-solution/members-area) installed.
- In custom field applications, `exclusions.items` override `applications.items`. If you assign a field to a member but exclude it from their pricing plan, they won't see the field.
- By default, custom fields are assigned to all members on a site. Use [Custom Field Applications](https://dev.wix.com/docs/api-reference/crm/members-contacts/members/member-management/custom-fields/custom-field-applications/introduction.md) to restrict access to specific members or groups.

## Terminology

- **Custom Field**: A user-defined field that extends the default member profile information.
- **System Field**: A Wix-defined field from the default member profile information.
- **Field Application**: Rules that determine which members can access specific custom fields.
- **Field Suggestion**: Recommended custom fields available for creation based on common use cases.