Change permissions to a specific user in Ubuntu 12.04 [closed]

How can I change the permission (555 or 755) to a user in a specific folder in Ubuntu 12.04. I used this command, but it didn't work

sudo chown -R username:group directory

Thanks,

If you want to change the permissions use this command (755 will grant the owner of the file read, write and execute permissions and read and execute permissions to group and other users ):

sudo chmod -R 755 directory

If you want to change ownership of a folder and it's subfolders and files

sudo chown -R username:usergroup directory

If the owner of a file or directory is let's say the user jofrey you want to grant him read and write permissions:

sudo chmod -R u+rw directory

You can learn more about permission numbers and what they mean from this image