Hi
In HTML, the form concept is simple and static. This is one reason why people often use client-side scripting, usually in JavaScript, to enhance the functionality of forms. In some cases, this is just fine: it might give extra comfort to some users, without disturbing others. But it is important to know the limitations. Specifically, one should never rely on JavaScript alone in the processing of data entered by user; to make sure things work reliably, such processing needs to be repeated by a server-side script.
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