create as built in functions

I have bunch of functions related to my applications and all are .m files. I don't want to copy each function in current working folder when I need those. I want to keep them in Matlab such that, I can access to those functions forever. i.e., I want to make my functions as like default functions within Matlab. How to do this?

Answer 1

[John D'Errico]

These functions will be your new friends:

addpath, savepath, pathtool, rmpath

Answer 2

[Wayne King]

You can use pathtool, to add the folder where those functions are and save that path for future sessions.