| Symbol(s) | Description |
|---|---|
| '...' | single quote - remove special meaning of all enclosed characters |
| "..." | double quote - remove special meaning of all enclosed characters except $ ' and \ |
| \ | backslash - removes special meaning of single following character |
| \ | backslash - also used for line continuation at the end of a long line |
| `command` | back quote - execute command an insert standard output at the location of the left-most back quote |
| Parameter | Description |
|---|---|
| $* | all parameters in the parameter list |
| $# | the number of arguments passed into the shell program, in other words, the number of parameters in $* |
| $n | the nthparameter in the list |
| $0 | the name of the program being executed, i.e. the 0th parameter |
| $$ | the PID of the program being executed |
| $? | the exit status of the last command executed |