The following table explains symbols that might be used in this book.
Table P–3 Symbol Conventions| 
 Symbol  | 
 Description  | 
 Example  | 
 Meaning  | 
|---|---|---|---|
| 
 [ ]  | 
 Contains optional arguments and command options.  | 
 ls [-l]  | 
 The -l option is not required.  | 
| 
 { | }  | 
 Contains a set of choices for a required command option.  | 
 -d {y|n}  | 
 The -d option requires that you use either the y argument or the n argument.  | 
| 
 ${ }  | 
 Indicates a variable reference.  | 
 ${com.sun.javaRoot}  | 
 References the value of the com.sun.javaRoot variable.  | 
| 
 -  | 
 Joins simultaneous multiple keystrokes.  | 
 Control-A  | 
 Press the Control key while you press the A key.  | 
| 
 +  | 
 Joins consecutive multiple keystrokes.  | 
 Ctrl+A+N  | 
 Press the Control key, release it, and then press the subsequent keys.  | 
| 
 ->  | 
 Indicates menu item selection in a graphical user interface.  | 
 File -> New -> Templates  | 
 From the File menu, choose New. From the New submenu, choose Templates.  |