5 Lexical conventions [lex]

5.6 Tokens [lex.token]

token:
identifier
keyword
literal
operator-or-punctuator
There are five kinds of tokens: identifiers, keywords, literals,13 operators, and other separators.
Blanks, horizontal and vertical tabs, newlines, formfeeds, and comments (collectively, “white space”), as described below, are ignored except as they serve to separate tokens.
[Note
:
Some white space is required to separate otherwise adjacent identifiers, keywords, numeric literals, and alternative tokens containing alphabetic characters.
— end note
]
Literals include strings and character and numeric literals.