 Web browsers follow the HTML display specification and for programmers' convenience ignore runs of white space when displaying them.This convention originally comes from the underlying SGML standard, which collapses multiple spaces because of the clear division between content and layout information.In order to force a web browser to display multiple spaces, a special character sequence must be used (such as "codice_1" for an en-space followed by a thin space, "codice_2" for an em-space, or "codice_3" for two successive full spaces).