On Mastering Echo

Outside of just typing stuff randomly into a green + black monitor, you might want to learn how to use some stuff that allows us to interact with a file without opening it.

For this, we have echo. Nominally this would print its input to the screen, but we can tell it to put it into a file as well.

To replace an entire file (or create one, if it doesn't exist yet):

echo 'new content' > file

To append to the end of a file:

echo 'last line of content' > file

To use multi-line addition (there are several ways to do this, look for more):

echo 'more\nthan\none' > file