Gaining a little definition...

Absolute Measurement --- measurements of fixed values that cannot be altered, expressed in finite terms. Examples: millimeter, points, picas

Relative Measurement
--- relationships defined by relative values. Examples: character spacing, ems and ens, leading

Points/Picas --- unit of measure used to measure the type size of a font.  (a pica is equal to 72 points, 6 picas equal an inch)

x-height
--- height of a lowercase ‘x.’ It is a relative measurement based on each typeface. used as a reference point in the layout of a design.

The em. The en
--- relative units of measure used to define basic spacing functions (em is equal to the point size of the font, the en is equal to half of an em)

Dashes (hyphen, en, em)
--- all are used in punctuation to provide a measurement for dashes.  (em is equal to the point size of a font, en is equal to half of an em, hyphen is equal to 1/3 of an em and is used to link words)

Alignments: Justifcation, Flush Left, Flush Right
--- the posistion of type within a text block, in both the vertical and horizontal planes. Flush Right-less common and more difficult to read, words are aligned flush the right side of a text block ending ragged on the left.  Flush Left-follows the principle of handwriting, text is aligned flush with the left side of the text box ending ragged on the right

Letterspacing
--- increasing the space between letters

Kerning
--- reducing the space between letters

Tracking
--- adjusts the spacing between characters

Word Spacing
--- standard word space is a percentage of the individual typeface’s em, and is thus a relative measurement

Widow
--- lone word at the end of a paragraph

Orphan
--- the last one or two lines separated from the rest of the body of text

Leading
--- the vertical spacing between lines of text

Indent, Fist Line Indent, Hanging Indent --- text moved in from the margin by a specified amount.  First Line Indent- the first line is indented from the body of text.  Hanging Indent- the first line of text is justified to the side of the text body while the remaining lines are indented.