HTML5 - email
It accepts only email value. This type is used for input fields that should contain an e-mail address. If you try to submit a simple text, it forces to enter only email address in firstname.lastname@example.org format.
<!DOCTYPE HTML> <html> <body> <form action = "/cgi-bin/html5.cgi" method = "get"> Enter email : <input type = "email" name = "newinput" /> <input type = "submit" value = "submit" /> </form> </body> </html>