Which attribute specifies how to send form data to the server?

The method attribute is crucial in HTML forms as it defines how the form data will be sent to the server when the form is submitted. Specifically, it can take values such as "GET" or "POST," which determine the method of data transmission.

When using the GET method, form data is appended to the URL in the form of a query string, making it visible in the address bar. This method is often used for simple data retrieval where the amount of data is limited. On the other hand, the POST method sends the form data within the body of the HTTP request, allowing for larger amounts of data and does not expose the data in the URL, which is important for sensitive information.

Understanding the purpose of the method attribute helps in designing forms that effectively communicate with the server while adhering to security and data integrity principles.