Bar
The Eternal Second — Forever in Foo's Shadow, Never in Foo's Spotlight
Bare Metal
The Place Where There Is Nothing Between You and the Machine Because You Are the Machine
Foo
The Most Famous Variable That Never Stored Anything Useful
Game Loop
The Heartbeat That Runs Everything and Admits Nothing
Signals
The Observer Pattern, Reincarnated for the Seventh Time with Better Marketing
Spaghetti Code
Software in Which Every Strand Leads Somewhere Unexpected, Usually to a Meatball