I.	Coreutils
--------------------------------------
	BASH
	====
	keys:
	  ^R
	  	- search backward in command history
	  ^G
	  	- return to the normal state
	  ^L
	  	- clear the screen
	  ^D	
	  	- logout
	  ^S	
	  	- scroll lock [sometimes, 4ex. on my laptop]
		- search forward in command history
	  ^Q	
	  	- unlock the screen [if ^S is scroll lock
		  4ex. on my laptop]
	
	utils:
	  ls	
	  	- list content of a directory
	  ls -l	
	  	- list content of a directory in more depth
	  cd {DIR}
	  	- change directory.
		  if DIR is not defined, change to $HOME
	  cd -
	  	- change to previous directory
	  file
	  	- identify the type of a file
	  stat {File}
	  	- get informations all information about a file
	  users
	  	- current users
	  pwd
	  	- 'print working directory'
	  find /directory -name file
	  	- search for a specific file
	  chmod -R u-wx+rX ./
	  	- change mode on user ['u', group 'g', others 'o']
		  to not write or execute, but give him a right
		  to read files and change directories ['X']
		  + [-R] - recursive

	networking:
	  ping -c X [host.domain.tld,IPAddress]
	  	- check if host.domain.tld or IP Address is active
		  via 'X' number of ICMP packets
	  netstat -t
	  	- print out active TCP connections
	  netstat -lt
	  	- print out daemons waiting for TCP connections
	  ssh-keygen
	  	- generate a RSA keypair for SSH key-based autentization.
		  ~/.ssh/id_rsa.pub sould be then exported to destination
		  server to ~/.ssh/autorizes_keys [do not confuse with
		  ~/.ssh/known_hosts!]
	  ssh-add
	  	- add newly generated keypair ~/.ssh/id_rsa
		  to our key database
	  ntpdate -s ntp.domain.tld
	  	- synchronize system clock with a server [4ex. tak.cesent.cz]
		  via Network Time Protocol and log to syslog facility [-s]
	
	VIM
	===
	keys:
	  i
	  	- insert
	  R
	  	- replace
	  Esc
	  	- quit editing mode [for commands],
		  enter non-interactive mode.
	  q'Key'
	  	- record a macro under the given key.
		  end recording by pressing 'q' again
		  in non-interactive mode.
		example: qq
		
	  @'Key'
	  	- play a macro recorded under the given key.
		example: @q
	  @@
	  	- replay last used macro
	
	commands:
	  :q!
	  	- force quit, do not save changes
	  :!command
	  	- execute a given command in system shell
	  :w
	  	- write [save the current document]
	  :w file
	  	- write to a given file
	  :wq
	  	- write and quit
	  :e!
	  	- undo changes to the last write [save]
	  :n
	  	- 'next' if editing multiple documents
	  :wn
	  	- write the changes and continue on the next document
		  if editing multiple files
	  :%s/^hello/hi/g
	  	- use sed on whole document [%s] and replace 'hello' from
		  the beginning of every line with 'hi'.
		vide man sed for wildcards

	  :help
	  	- if lost, help is still available

	GPG
	===
	commands:
	  gpg --list-keys {Key_ID}
	  	- list all keys in your key database.
		  if Key_ID defined, list only this key.
	  gpg --gen-key
		- generate new keypair
	  gpg --export Key_ID -a -o ~/key.aa.pub
	  	- export Key_ID key to /home/$USER/key.aa.pub
		  as an ASCII armored file [uuencode like]
	  gpg -esa --for-your-eyes-only file
	  	- *E*ncrypt, *S*ign and *A*SCII armor the output
		- If 'For Your Eyes Only', GPG will refuse to save the file
		  unless the --output option is given.
	  gpg --decrypt --output result.file crypted.file
	  	- decrypt [and verify signature, if present] given file
		  and save output to result.file.
II. Debian-specific
-------------------------------------

	 update-alternatives --set editor /usr/bin/vim.tiny
	 	will link /etc/alternatives/editor to /usr/bin/vim.tiny "The Debian Way"