Convention | Explanation |
bold | Bold typeface usually indicates elements of a graphical user interface, such as menu names, dialog box names, commands, options, buttons, and so forth. Bold typeface is also applied occasionally in a standard typographical use for emphasis. |
italics | Italics indicate a variable that must be replaced with an appropriate value. For example, user_name would be replaced with an actual user name. Italics is also applied occasionally in a standard typographical use for emphasis, such as for a book title. |
cAsE | Uppercase text is used typically to improve readability of code syntax, such as SQL syntax, or examples of code. Case is significant for some operating systems. For such instances, the subject content mentions whether literal text must be uppercase or lowercase. |
monospace | Monospace text is used typically to improve readability of syntax examples and code examples, to indicate results returned from code execution, or for text displayed on a command line. The text may appear uppercase or lowercase, depending on context. |
', ", and “ ” | Straight quotes, both single and double, are used in code and syntax examples to indicate when a single or double quote is required. Curly double quotes are applied in the standard typographical use for quotation marks. |
| | The vertical rule indicates an OR separator to delineate items for which you must choose one item or another. See explanation for angle brackets below. |
[ ] | Square brackets indicate optional items. Code syntax not enclosed by brackets is required syntax. |
< > | Angle brackets indicate that you must select one item within the brackets. For example, <yes | no> means you must specify either “yes” or “no.” |
. . . | Ellipsis indicates that the preceding item can be repeated any number of times in succession. For example, [parameter . . .] indicates that parameter can be repeated. Ellipsis following brackets indicate the entire bracketed content can be repeated. |
::= | The symbol ::= means one item is defined in terms of another. For example, a::=b means that item “a” is defined in terms of “b.” |
%string% | A variable defined by the Windows operating system. String represents the variable text. The percent signs are literal text. |
$string | An environment variable defined by the Linux operating system. String represents the variable text. The dollar sign is literal text. |