How to prevent emacs annoying habit of adding the current word to any command buffer?

Whenever I c-x c-f, emacs adds the current word at the cursor point to the c-x c-f.

I believe this is probably due to ido.

How can I turn this off开发者_如何学运维?

It's an ido option that's usually not activated by default. It can be turned off with this line:

(setq ido-use-filename-at-point nil)