file.m is a Mathematica package file.
CellLabel is an option for Cell which gives the label to use for a particular cell.
ClearSystemCache[] clears internal system caches of stored results.
Continue[] exits to the nearest enclosing Do, For, or While in a procedural program.
First
(Built-in Mathematica Symbol) First[expr] gives the first element in expr.
Last
(Built-in Mathematica Symbol) Last[expr] gives the last element in expr.
NotebookClose[notebook] closes the notebook corresponding to the specified notebook object. NotebookClose[] closes the current evaluation notebook.
NotebookDelete[notebook] deletes the current selection in the notebook corresponding to the specified notebook object. NotebookDelete[] deletes the current selection in the ...
NotebookFileName[] gives the file name of the current evaluation notebook. NotebookFileName[nb] gives the file name for the notebook specified by nb.
OverBar
(Built-in Mathematica Symbol) OverBar[expr] displays with a bar over expr.