Ubuntu Vivid: Things you should change after fresh setup

If you Setup Ubuntu 15.XX on a PC there are a few things to change:

open a Gnome Terminal an run (# Comments):

• $sudo apt-get update && apt-get dist-upgrade #Pull Updates
• $sudo adduser CrazY12U$ERNAME # Create a crazy Username (Standarduser, no sudo, no lpadmin) for daily work! to prevent social engineering Hacks
• $sudo chmod 700 /home/* # to prevent that other users look into each other homes! (check root home to „ls -l /root)
• $sudo passwd root # SET long Password (min.15 digits) for the root User to prevent PC recovery Console Access without Password!!! Keep Password save!
• $sudo apt-get install gufw  #Installs Firewall Dialog to easy setup a Firewall
• $sudo apt-get install midori chromium-browser # to have 3 different browsers to open stream sites with plugins same time
• $firefox -P #to create a Firefox Profile on Path /tmp which is deleted after every reboot, cause /tmp is on tmpfs (RAM)
• $sudo apt-get install pidgin # to use pidgin chat (icq+facebook..)
• $sudo apt-get install cpufrequtils #Auto sensing the CPU frequency to the load
• $sudo apt-get install rsync # to sync home to a NAS Server in your Network over ssh encrypted! with „$rsync -av /home/user/ server:/home/user“
• $sudo apt-get install gimp # to get a good Photoeditor
• $sudo apt-get install filezilla # to have a nice FTP/FTPS-Client
• $sudo apt-get install cups-pdf # to print notes/Websites from Browser into PDF document files for offline read (Paperless office)
• $sudo apt-get install ssh # to have a secure remote access to your PC from everywhere (open incomming Port 22 with gufw)
• $sudo gedit /etc/sshd/sshd_config and change:

AllowUsers yourusername #to allow only one user to login!!
PermitRootLogin no #disallow root to login!!! 
PasswordAuthentication no # disallow login without passwords
#if you have a ssh-pub-key!! then..
PubkeyAuthentication yes
AuthorizedKeysFile  %h/.ssh/authorized_keys