$NewSymbol is a global variable which, if set, is applied to the name and context of each new symbol that Mathematica creates.
In doing a calculation with Mathematica, you usually go through a sequence of steps. If you want to, you can do each step on a separate line. Often, however, you will find it ...
AbortQ
(Mathematica LibraryLink C Function) mint AbortQ () returns TRUE if Mathematica is in the process of an abort.
Mathematica includes functionality to factor polynomials symbolically.
Close All closes all open notebooks (Windows only).
Close closes the current notebook.
Enter Selection places a selection into the Search for: field of the Find dialog box.
Exit causes Mathematica to quit.
InputForm Display displays the selection in Mathematica InputForm without interpreting it.
Merge Cells combines selected cells into one cell.