Bash, also known as the Bourne again shell, is found on Unix and Linux operating systems. It is used on the command line interface and in scripts saved as text files.
Variables can be set in Bash scripts with the assignment operator '=' and later used with the '$' character. An example:
echo $environment
environment=development
echo $environment
Output:
development
Use the '>' redirection character
to delete the contents of the file and
output the previous command's sandard out
to the file.
example:
ls > outfile.text
Use the '>>' rediection characters to
append to the file.
example:
ls >> outfile.text
To append standard out and standard
error to the same file redirect standard out
like above and redirect standard error
to the same file with 2>&1
example:
ls >> outfile.text 2>&1
A great explanation of this double
redirection is in this StackOverflow answer.