3.1.6 Blanks vs. Spaces Note that the description differs between “blanks” and the <space> character. A blank is any character that might be used as “whitespace” to separate text into groups of characters. The <space> character is only one of several possible blanks. When this text says “blank” it means any one from a set of characters that are used to separate visual characters into words. When this text says <space>, it means one particular blank, that which is generally bound to the spacebar on a normal computer keyboard. All implementation can be trusted to treat the <space> character as blank. Additional characters that might be interpreted as blanks are <tab> (horizontal tabulator), <ff> (formfeed), <vt> (vertical tabulator), <nl> (newline) and <cr> (carriage return). The interpretation of what is blank will vary between machines, operating systems and interpreters. If you are using support for national character sets, it will even depend on the language selected. So be sure to check the documentation before you assume anything about blank characters. Some implementations use only one blank character, and perceives the set of blank characters as equivalent to the <space> character. This will depend on the implementation, the character set, the customs of the operating system and various other reasons.