Now, there are lots of redirection symbols that you can use, and here are some of them:
means open a file for reading and associate with STDIN.
Means use the current input stream as STDIN for the program until token is seen. We will ignore this one until we get to scripting.
means open a file for writing and truncate it and associate it with STDOUT.
means open a file for writing and seek to the end and associate it with STDOUT. This is how you append to a file using a redirect.
means redirect FD n to the same places as FD m. Eg, 2>&1 means send STDERR to the same place that STDOUT is going to.