ubuntu - what are these codes which are used to edit configure files? -

almost every time try edit configure files of softwares have use codes , commands have no idea them. example when try edit gvim configure file have use specific codes or when try auto mount partition in fstab have use codes or when trying edit ~/.emacs had use codes these(not same)

(require 'cl)        (lexical-let ( (cols color-theme-choices) )       (defun test-win-sys (frame)         (let ( (color-theme-is-global nil) )           (select-frame frame)           (eval (append '(if (window-system frame))                  (mapcar (lambda (x) (cons x nil)) cols)))))) 

which don't have idea called. want learn emacs , ubuntu , expert. question has 2 parts: 1- people learn these codes? 2- these programming language? called?

you won't become "an expert" overnight.

1. there many ways configure programs in unix world. language, if any, used change 1 program other there no single starting point you.

2. in unix world, most programs come 1 or more "manual page(s)" can read man command. canonical entry point when have use/configure program don't know , first place should @ when stuck.

   type command below manual cron:

   $ man cron 

   how read manual page vim?

   also, (very) condensed version of manual page available when add --help flag command:

   $ bash --help 

3. "simple" programs cat don't need documentation beyond what's in man cat more complex programs vim or emacs come extensive inline documentation. reading documentation necessary if want configure programs correctly.

   the "splash screen" when $ vim or $ emacs tells how access inline documentation.

4. many programs come "default" or "sample" configuration file; reading manual tell if , file , how enable it.

5. you see acronym lot, allow me first 1 rtfm.