Shell and such

sh.txt

What is the terminal
	a program that emulates the terminal
	iterm or terminal most commonly
	windows: https://www.quora.com/How-do-I-open-terminal-in-windows
	
What is the shell
	a program that takes commands from the keyboard and gives them to the operating system to perform
	operating system is what "does all the things"
		performs tasks
		recognizes keyboard input
		sends things to the screen to display
	talk to the operating system through a terminal or through a gui application/screen

What do you use it for
	programming
	many things you can do in the editor (manage files)
	but some programs you can only interact with through the terminal
	another tool in your toolbox
		faster
		more effective
		tons to learn 
			- there must be a better way! 
			- warning signs: repetition, same steps

bash and zsh
	- bourne again shell
	- bash stays closer to POSIX (standard for operating system)
	- bash stays compatible for more systems
	- zsh does not avoid interactive features, like completion
	- prompt, left and right prompt
	- shared histories across terminals
	- let's install zsh
		- use which zsh to see if you have it
	
directory structure
	- home directory
		- echo $HOME (first command!)
		- come back to this to demonstrate different shells

understanding the path
	- echo $PATH
	- whenever you run a command, your shell will look through the files in your path to find what to execute
	- ls -la /usr/local/bin
	- find a program (brew?) and execute it with the full path
	- if you are unsure if something has been installed properly, run "which" 

navigate the terminal
	- cd (change directory) takes you $HOME
	- cd - takes you back to the previous dir

different shells
	- change env variable $HOME to something else
	- navigate somewhere
	- do cd $HOME
	- get to the new place
	
	- open up another shell, echo $HOME
	- is it taking them to the same place
	- why not?
	
sourcing of files	
	- when different shells open up, they source the same config
	- exporting a var locally in a shell won't set it for others
	- the context are the config files and the shell is the scope
	- .{bash,zsh}rc, .{bash,zsh_profile
	- _profile runs once on startup when you login
	- bashrc is run when you start a new shell
	- best practice is to source your bashrc in your bash_profile and keep all configs in bashrc

aliases
	- very useful for things you are typing a lot
	- alias hey="echo \"what\""

set up your dotfiles
	- have all your configs in a version controlled repo
	- easier to set up your computer next time
	- cd
	- mkdir .dotfiles
	- symlinks to .gitignore and .gitconfig
	- look at "man ln" to find out how to create them
	- mkdir .dotfiles/zsh
		- where I keep all my zsh files
	- symlink zsh_profile.zsh and zshrc.zsh 
		- copy over the contents in different file before
		- need to keep the extension!
	- add prompt
		- source .dotfiles/zsh/prompt.zsh in the zshrc.zsh
		- prompt and rprompt
		- colors %F{color}%f
		- can use bash in the prompt 
		- google is your friend
	- source aliases
		- git aliases
		- directory jumping 
		- common things you do
	- functions
		- download multiple videos
		- ??