diff --git a/.vim/undo/.gitignore b/.vim/undo/.gitignore
new file mode 100644
index 0000000..e69de29
diff --git a/.vimrc b/.vimrc
index 8874db6..6d78368 100644
--- a/.vimrc
+++ b/.vimrc
@@ -68,6 +68,14 @@ filetype plugin indent on
 
 " exrc allows loading local executing local rc files.
 " secure disallows the use of :autocmd, shell and write commands in local .vimrc files.
+
+" save undo trees in files
+set undofile
+set undodir=~/.vim/undo
+
+" number of undo saved
+set undolevels=10000
+
 """"""""
 " SAVE "
 """"""""
@@ -284,7 +292,7 @@ function! TagInNewTab()
         execute 'tag ' . word
 endfunction
 
-map    <C-I>    :call TagInNewTab()<CR>
+map    <C-S-I>    :call TagInNewTab()<CR>
 
 """""""""
 " PASTE "