word completion

[Miki Grahame]

I'm doing some coding using repetitive long variable names. Is there
some emacs command that can automatically complete these for me so
I don't have to type them out in full every time? I.e. after typing a
few letters it guesses what word I'm typing.

(I've searched the emacs manual but can only find infomation about doing
auto completion in the mini-buffer.)

Thank you,

Miki