This article is from the Frequently Asked Questions for Linux, the Free/Open Source UNIX-like operating system kernel that runs on many modern computer systems. Maintained by David C. Merrill with numerous contributions by others. (v1.0).
A: If ls is displaying in color and you haven't told it to, you probably have an alias configured for it. Some distributions ship this way by default.
The shell command, unalias ls, should completely unset the configuration that some distributions provide as standard.
To permanently make this change, check your initialization script, .bashrc.
A: To change the colors, rather than removing them, refer to the ls man page (man ls).