# What user is currently logged in to create a directory or file, he belongs to the main group and who is
# Users to have several directories permissions
# Ll -d permission to view the current directory information
#r: You can view subfolders under the name of the directory, subdirectory
#w: You can create in the directory, delete, rename
#x: can cd to the directory
# If the current directory does not have permission, does not affect other existing directory permissions
#chown owner, is a group /test.text (genus modified file owner and group attributes)
# Change only the owner: chown parameters is a group
# Only change is in the group: chown is a set of parameters.