UNIX for Dummies Questions & Answers

(Keeping in mind I know very little about Unix...)
When I am typing this out (without copy-pasting the whole thing) to get my screensaver onto my background:

/System/Library/Frameworks/ScreenSaver.framework/Resources/ScreenSaverEngine.app/Contents/MacOS/ScreenSaverEngine -background

I start something like this:
cd /System/ [Enter]
cd Library/ [Enter]

I go through opening all the files and get stuck trying to open the screensaver into the background. (cd ScreenSaverEngine -background does not work so I assume it's 'open')
open ScreenSaverEngine -background
LSGetApplicationForInfo() failed with error -10814 while trying to determine the application with bundle identifier ackground.

Just hoping somebody can tell me how to run the screensaver into the background without having to copy paste the line. (Although it's faster, I prefer going through the steps myself)

Try typing './ScreenSaverEngine --help'. If you're lucky it might tell you what its options are.

Actually i just tried typing in what you said './ScreenSaverEngine' but then
added -background and it worked './ScreenSaverEngine -background'
why does the period have to be added (b/c just '/ScreenSaverEngine -background' does not work

/ tells it to go all the way to the root of the disk. You'd have to type the whole thing:

/System/Library/Frameworks/ScreenSaver.framework/Resources/ScreenSaverEngine.app/Contents/MacOS/ScreenSaverEngine -background ...which actually would work, if you wanted to make it all on one line. You wouldn't even need to CD that way, I think.

You need ./ because the shell doesn't run things in the current directory. You have to tell it 'in the current directory' explicitly. This is a security feature (so someone can't drop files in your directory and have you unknowingly run them.)