Websites using some form of Captcha technology on them.
PHP is a widely-used general-purpose scripting language that is especially suited for Web development and can be embedded into HTML.
UTF-8 (8-bit UCS/Unicode Transformation Format) is a variable-length character encoding for Unicode. It is the preferred encoding for web pages.
The http-equiv attribute provides an HTTP header for the information/value of the content attribute. The http-equiv attribute can be used to simulate an HTTP response header.