I have tried to parse a file language_data.txt, which is edited by Emacs. The different columns are separated by tab characters.
But when I opened the file, I found that each of the tab characters had been replaced by many space characters. For example:
en_US shiphrah 02005 book reader no connection
en_US shiphrah 02006 user reader no connection
How to insert a tab character in Text mode?
C-q <tab>
C-q insert the next character as a raw character
quoted-insert, so more specifically, this is M-x quoted-insert <tab>
In addition to answer given: Check value of indent-tabs-mode, customize it if needed.
Several hooks use it's value doing translations TAB-Blank.
If you want TAB key to insert a tab character, add this to your ~/.emacs
(global-set-key (kbd "TAB") 'self-insert-command);
More helpful info on emacs + TAB : https://web.archive.org/web/20160312104535/http://vserver1.cscs.lsa.umich.edu/~rlr/Misc/emacs_tabs.htm
Addition to @Vash2593 answer.
If you want to insert tab to more than one line. You can use indent-rigidly which is bound to C-x TAB. Then you can move the indentation interactively with S-left or S-right.
Or you can supply with emacs universal argument C-u. e.g C-u 4 C-x TAB to add 4 spaces. C-u -4 C-x TAB to remove 4 spaces.
This is very handy when it comes to formatting codes in social forums. Which need 4 spaces indent.
