OS user creation

commands

Create a user for your app, named hello and assigned to a system group called webapps.

$ sudo groupadd --system webapps
$ sudo useradd --system --gid webapps --shell /bin/bash --home /webapps/hello_django hello

I like to keep all my web apps in the /webapps/ directory. If you prefer /var/www/, /srv/ or something else, use that instead.
Create a directory to store your application in /webapps/hello_django/ and change the owner of that directory to your 
application user hello

$ sudo mkdir -p /webapps/hello_django/
$ sudo chown hello /webapps/hello_django/

$ sudo su - hello (gerek yok sadece kullanıcı hesabı değiştirmeye yarıyor)

Allowing other users write access to the application directory
Your application will run as the user hello, who owns the entire application directory. If you want regular user to 
be able to change application files, you can set the group owner of the directory to users and give the group write 
permissions.

$ sudo chown -R hello:users /webapps/hello_django
$ sudo chmod -R g+w /webapps/hello_django

You can check what groups you’re a member of by issuing the groups command or id.

$ id
uid=1000(michal) gid=1000(michal) groups=1000(michal),27(sudo),100(users)

If you’re not a member of users, you can add yourself to the group with this command:

$ sudo usermod -a -G users `whoami`
Group memberships are assigned during login, so you may need to log out and back in again for the system to
recognize your new group.