Each Linux/Unix command has 3 communication channels: input, output and error. The output can be filtered and then redirected and by this way parts of it can be captured, depending on the needs.
Redirecting the output to a file, using > or >>:
> – if the file mentioned does not exist it will be created, and if it does exist it will be overwritten;
ls -la > testfile1.txt
>> – if the file mentioned does not exist it will be created, and if it does exist the information it...