Help > Documentation Center (Mathematica Menu Item)

Documentation Center opens the Wolfram Mathematica Documentation Center.

Format > Word Wrapping > Don't Word Wrap (Mathematica Menu Item)

Don't Word Wrap turns word wrapping off.

Cell > Cell Properties > Editable (Mathematica Menu Item)

Editable toggles whether a cell can be edited or not.

Insert > File... (Mathematica Menu Item)

File inserts the contents of a file at the insertion point.

Insert > Table/Matrix > Make Spanning (Mathematica Menu Item)

Make Spanning combines the selected entries from a formatted grid into a single spanning entry.

[Right-click] > Open in New Window (Mathematica Menu Item)

Open in New Window opens the selected (or clicked upon) documentation link in a new help viewer window.

Cell > Cell Properties > Open (Mathematica Menu Item)

Open toggles a cell between open and closed.

Edit > Paste (Mathematica Menu Item)

Paste inserts the current contents of the clipboard at the insertion point.

Insert > Picture (Mathematica Menu Item)

Picture inserts a picture from a file or inserts an empty graphic at the insertion point.

File > Print Selection... (Mathematica Menu Item)

Print Selection prints a selection.