The name and ID of HTML can be compared to the name and ID number of an ID card.

The ID number is unique and an ID only appears once.

The name is repeatable and can appear multiple times.

In CSS, both have the function of identifying HTML elements. Name is represented by a period. and ID is represented by a pound sign #.

Generally, name is used for the style definition of common elements that appear multiple times, and ID is used for the style definition of unique elements.

In forms, since some controls have multi-element features, such as radio checkbox, etc., using ID is not convenient for submitting form data. In addition, the browser will set the request sent to the server based on the name. Therefore, in the form, name is used to submit data.

Of course, in actual HTML, ID can be completely omitted. A separate class can also replace ID. However, in JS, it is impossible to directly access HTML elements through class. Defining ID facilitates related operations.