Less-commonly used input types include the following:

hiddenContains a value, in the form <input type="hidden" value="x">. Must be placed between opening and closing <form> tags. Used to pass a value to the form parser that the user does not enter themselves. Commonly used in CGI scripts (for example, to pass the eMail address to send the parsed form information to) or multi-part forms.
imageA substitute for the submit type, replacing the submit button with an image. Takes the form <input type="image" src="image.gif">
passwordUsed to obscure the entry of text from "over-the-shoulder" social hackers. Visually replaces text entered into the text box with dots or asterisks. Does not encode or encrypt the entered text - it is still sent as plaintext over the Internet. Should have a switch option, if possible.

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