I am attempting to follow privateeyepi's tutorial on how to set up a home webcam.
The first instruction is mkdir /home/webcam. Pi's response = mkdir: cannot create
directory '/home/webcam': Permission denied
Just to let you know, the term you're looking for for the command line language is "Bash shell", if you ever feel the need to look up a tutorial on it - most Unix-based systems use similar command sets to it.
What "sudo" does specifically is to run the next command on the line with superuser permissions - the "pi" user doesn't have permission to modify or make files in the root directory by default, but by adding "sudo" ('superuser do'), you tell Bash to allow this action temporarily.