Form URL encoding
From Just Solve the File Format Problem
Form URL encoding (often known by its MIME type application/x-www-form-urlencoded) is a format mainly used for transferring form data (information typed into a form on a web page) from a web browser to a web server.
Form URL encoding uses a form of Percent-encoding in which a space character is allowed to be encoded as a "+" character. It can constitute the body of an HTTP "POST" message, or the "query string" portion of a URL (see URL encoding).
Form URL encoding can be used for binary data, but it is inefficient. The alternative is Multipart/Form-Data.
