Visualforce is a framework for creating custom user interfaces in Salesforce. It is a component-based framework that allows developers to build custom pages and components using HTML, CSS, and Apex, the proprietary programming language of Salesforce.

The following are some of the key uses of Visualforce:

Customizing User Interfaces: Visualforce provides a way to create custom pages and components that can be used to extend or replace the standard Salesforce user interface.

Building Mobile Applications: Visualforce provides support for building mobile applications that can run on any device, including smartphones and tablets.

Enhancing Functionality: Visualforce provides a way to add custom functionality to Salesforce that may not be available in the standard user interface, such as custom data entry forms, reporting, and dashboards.

Integrating with External Systems: Visualforce can be used to build integrations between Salesforce and other systems, such as integrating with a third-party payment system or a custom database.

Building Communities: Visualforce provides support for building custom pages and components for Salesforce Communities, allowing organizations to build custom portals for their customers, partners, or employees.

Overall, Visualforce is a powerful tool for customizing and extending the functionality of Salesforce, providing a way for developers to build custom pages and components that can meet the unique needs of their organization.