diff --git a/README.org b/README.org
index b4908f4..cf354dd 100755
--- a/README.org
+++ b/README.org
@@ -26,33 +26,45 @@ Emacs is free software project with many years of development and a very active
 
 ** Contents
 
+*** First steps
+
   * [[./doc/init_emacs.org][How to initialize emacs]]
   * [[./doc/help.org][Find manuals and help to use emacs]]
+  * [[./doc/packages.org][Dealing with packages in emacs]]
+  * [[./doc/dired.org][How to use 'dired']]
+  * [[./doc/links_emacs.org][Links to learn more about emacs]]
+  * [[./doc/compile.org][Compiling emacs in GNU linux]]
+
+*** How to 'move' in emacs buffers
+
   * [[./doc/movement.org][Movement and text edition]]
   * [[./doc/using_meta.org][Using 'meta' (M-x)]]
   * [[./doc/using_alt.org][Using 'Alt' (M)]]
   * [[./doc/using_ctrl_x.org][Using 'CTRL + x']]
   * [[./doc/using_ctrl.org][Using 'CTRL']]
-  * [[./doc/ddbb_use.org][Using ddbd to keep your contacts]]
+
+*** Working with files
+
+  * [[./doc/ido.org][Using 'ido' mode]]
+    
+*** Emacs org-mode
+
   * [[./doc/org_intro.org][Introduction to emacs org-mode]]
   * [[./doc/orgbabel.org][Introduction to org babel: literating programming in emacs]]
-  * [[./doc/dired.org][How to use 'dired']]
-  * [[./doc/packages.org][Dealing with packages in emacs]]
-  * [[./doc/R_in_emacs.org][Using R in emacs]]
   * [[./doc/citations.org][How to include bibliograpic references in org documents]]
-  * [[./doc/links_emacs.org][Links to learn more about emacs]]
-  * [[./doc/ledger.org][Using ledger in emacs]]
-  * [[./doc/compile.org][Compiling emacs in GNU linux]]
   * [[./doc/org_images.org][Including images in org files]]
 
+*** Statistics and data science
+
+  * [[./doc/R_in_emacs.org][Using R in emacs]]
+  * [[./doc/python_in_emacs.org][Using Python in emacs]]
+
+*** More nice things to know
+
+  * [[./doc/ledger.org][Using ledger in emacs]]
+
 ** Contenido
 
  * [[./spa/porque_usar_emacs.org][Una breve introducción al uso de emacs]]
 
-** Contact
 
-[[https://www.onecluster.org/][Onecluster]] is a community of people who enjoy learning and sharing experiencies about free-software {libre as in freedom}.
-
-For questions, comments, doubts about free-software visit our [[https://ayuda.onecluster.org/][Discourse]]
-
-Please let us know if you liked, used or have any question or suggestion on how to improve this tutorial.
diff --git a/doc/citations.org b/doc/citations.org
index f8762f7..6a183d5 100755
--- a/doc/citations.org
+++ b/doc/citations.org
@@ -3,7 +3,6 @@
 #+bibliography: ../bib/lepto-ref.bib
 #+options: toc:nil num:nil author:nil
 
-
 * How to make citations using Emacs org-mode
 
 It is possible to include bibliographic citations within org documents.
diff --git a/doc/help.org b/doc/help.org
index d400079..37a9f8b 100755
--- a/doc/help.org
+++ b/doc/help.org
@@ -20,12 +20,12 @@ the manuals.
 
 : C-h i
 
-To search for files within the manuals, you can use 'ALT' then 'm' (menu) and
+To search for files within the info version of manuals, you can use 'm' (menu) and
 then 'some words you need to find'.
 
 To search 'awk' manual within info manuals:
 
-: M m awk
+: m awk
 
 ** man
 
diff --git a/doc/ido.org b/doc/ido.org
new file mode 100644
index 0000000..ed7c10a
--- /dev/null
+++ b/doc/ido.org
@@ -0,0 +1,45 @@
+#+date: 2023-07-19
+#+options: toc:nil num:nil author:nil
+
+* Ido mode
+
+'Ido mode' stands for "interactively do". It's a package of emacs used to switch
+between buffers and find (open or create) files.
+
+To activate the mode you may use 'M-x' (keys: "Alt" + "x" ):
+
+- ~M-x ido-mode~: initializes ~ido~ for one emacs session.
+
+To activate ~ido~ for every emacs session, you may include the following in the
+emacs initialization file (e.g., ~.emacs~, ~.emacsd/config.org~ ):
+
+#+begin_example emacs-lisp
+  (require 'ido)
+  (ido-mode t)
+#+end_example
+
+** Open files and visit other buffers
+
+After activating ~ido~ using the keybindings '~C-x + C-f~' will execute the function
+'ido-find-file'.
+
+Also, using 'C-x' and then  'b' will open options to visit any open buffer in
+the session.
+
+#+begin_comment
+*Note* that visiting a file with ido (C-x C-f) will search for the name of the
+file everywhere, wich can be annoying if you want to create files with the
+same name in different directories.
+
+To avoid this behavior, you may use 'M-x ido-find-file-in-dir' to precisely
+indicate the place where you want to create the new file.
+
+If you use 'C-x C-f' you may use [[https://stackoverflow.com/questions/23741014/how-to-stop-auto-complete-from-overwriting-a-file-that-is-similarly-named]['C-j']] after to avoid emacs visit a file with
+the same name, and instead create a new file.
+
+#+end_comment
+
+** References
+
+- [[https://stackoverflow.com/questions/23741014/how-to-stop-auto-complete-from-overwriting-a-file-that-is-similarly-named][Avoid overwriting files with similar name while using ido]]
+#+print_bibliography: