:  | A colon links command keywords together to form commands. The colon is not an actual part of the keyword, but is a signal to the SCPI interface parser. A colon must precede a root keyword immediately following a semicolon (see Notational Examples).  | 
;  | A semicolon separates commands if multiple commands are placed on a single program line.  | 
[ ]  | Square brackets enclose one or more optional keywords.  | 
{ }  | Braces enclose one or more keyword or command parameters that may be included one or more times.  | 
|  | A vertical bar indicates “or” and is used to separate alternative parameter options. Example: ON | OFF is the same as ON or OFF.  | 
< >  | Angle brackets enclose parameter descriptions.  | 
::=  | Means “is defined as” For example: <a>::=<b><c> indicates that <b><c> can replace <a>.  | 
sp  | Space, referred to as white space, must be used to separate keywords from their associated data parameters. It must not be used between keywords or inside keywords.  | 
XXX  | Indicates a root command name  |