You want to redirect the output of a command somewhere:
- 
    stdout to file $ your_command > output.txt
- 
    stderr to file $ your_command 2> output.txt
- 
    stdout to stderr $ your_command 1>&2
- 
    stderr to stdout $ your_command 2>&1
- 
    stdout and stderr to file $ your_command &> output.txt
 
 