HTML5 required and pattern are not a security feature

In HTML5, you can provide a required attribute to ensure a certain field has been filled out before a form can be sent off.

<input id="tac" required name="tac" type="checkbox">
<label for="tac">I have read the terms and conditions</label>

You can go even further and define a pattern that the value of the field needs to comply with before it can be sent off. For example, the following only allows entries that are either upper or lowercase a to z letters.

<label …

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