Text Justification controls justification (word spacing) of wordwrapped cells.
Natural Spacing introduces no additional spacing, resulting in ragged margins.
Full Justification introduces enough additional spacing to each line to make it fill the full width of the column, resulting in flush margins. This is a commonly used style, but results in hard-to-read text.
The other justification settings apply varying degrees of justification, resulting in less ragged, but not fully flush margins.
The commands in this submenu set the option TextJustification on the selected cell object(s) or on text within a cell.