What does TCX stand for in theme customizer for wordpress theming? They use it in the following tutorials:
http://wp.tutsplus.com/tutorials/theme-development/a-guide-to-the-wordpress-theme-customizer-adding-a-new-setting/
http://wordpress.thekb.net/wordpress-tutorial/a-guide-to-the-wordpress-theme-customizer-adding-a-new-setting/
Why is it there? Can I remove it?
It is just an acronym that the person is using for his own custom functions. The name can be changed to whatever you want so long as you change the other function references to match the declared one.
It is common for wordpress developers to add prefixes to their functions because of the lack of object oriented framework as well as the worry about running into conflicts with other plugin/theme functions. These prefixes are commonly the developers initials.
There isn’t a need to change the function name.