Why does VIM highlight some words?

Question

I noticed that with different colorschemes VIM is underlining/highlighting some words. Why is this and how to turn it off ?

Answer 1

Most filetypes (like python) in Vim come with a syntax that defines highlight groups (see them via :highlight). A colorscheme then provides combinations of foreground / background color and/or formatting like bold and italic, for terminals, color terminals, and/or GVIM.

Choose a colorscheme that you find visually appealing; some come with Vim, many more can be found on the Internet, most at http://www.vim.org/.

If you're just annoyed by one or two minor things in a particular colorscheme, you can modify the items via the :highlight command. To disable a highlighting, use, e.g.

:highlight clear Statement

or (when the group is linked to another group, effectively inheriting its appearance)

:highlight link Statement NONE

(These must be issued after the :colorscheme command that sets your preference.)