Space Lengths:
              No Space: ][
      Zero Width Space: ]​[
            Hair Space: ] [
          1/6 Em Space: ] [
            Thin Space: ] [
          1/4 Em Space: ] [
         Regular Space: ] [
          1/2 Em Space: ] [
              En Space: ] [
          Figure Space: ] [
              Em Space: ] [
         Tab Character: ]	[

Spaces needed to make a certain length:
         Tab Character: ]	    [ (1 + 4 hairsp)
              Em Space: ]    [ (4)
              En Space: ]        [ (8)
          1/2 Em Space: ]                [ (12 + 4 hairsp)
         Regular Space: ]                [ (16)
          1/4 Em Space: ]                [ (16)
            Thin Space: ]                      [ (21 + 1 hairsp)
          1/6 Em Space: ]                      [ (21 + 1 hairsp)
            Hair Space: ]                                                                [ (64)
      Zero Width Space: ][ (inf (actually 2048))

Unbackspaceablee (uses 10000 zero width spaces between the 2 e's at the end)

This is a soft hy­phen­a­ted piece of text that has a word "on­o­mat­o­poe­ia" in it that might get split, and may­be "pneu­mo­no­ul­tra­mi­cro­sco­pic­sil­i­co­vol­ca­no­con­i­o­sis" will get split as well. A soft hy­phen on­ly dis­plays when it is at the end of a line.