Absolute Measurement: Fixed values expressed in finite terms and cannot be altered.
Relative Measurement: Measurements linked to type size. Example: leading changes according to type size in order for letters not to mix in with each other.
Points/Picas: A point is a unit of measurement used to measure the type size of a font referring to the height of the type block. A pica is a unit of measurement equal to 12 pts. Is more commonly used for measuring lines of type.
x-height: the height of the typeface in reference to the height of the lowercase 'x'. It's measured by the baseline to the meanline of the typeface.
The em. The en: The em is the unit of measurement in typesetting that defines basic spacing functions and is linked to the size of type. Used for defining paragraph indents and spacing. It also equals the size of the type. (72 pt font = 72 type.) The en is the measurement that is half of em. (72pt type = 36pt type)
Dashes (hyphen, en, em): All distinct but similar functions. An en is half of an em. A hyphen is 1/3 of an em.
Alignments: Justifcation, Flush Left, Flush Right: How the line of a text refers to the column. Justification is when all of the text are of equal length from the column. It makes for clean edges.
Flush Left is the the entire text is shifted to the left causing for equal length from the left side of the text to the column and unequal from the right side to the column. Flush Right is the exact opposite of that. Left provides an organic flow of the language while right helps provide the designer with great use of captions, sidebars, notes, etc.
Example of a Flush Left Alignment -- >
Letterspacing: Increasing the amount of space between letters.
Kerning: Reducing the amount of space between letters.
Tracking: Adjusting the amount of space between characters.
Word Spacing: "a percentage value of an em" It is relative to the size of the type. It is the space between the letters and is fixed in the postscript information of a typeface. However, it can be altered by changing the hyphenation and justification values.
Widow: The final line of a paragraph that is left at the beginning of the next page or column by itself.
Orphan: A single word that is either left at the end of the paragraph on its own line or the first word of a text that is left at the bottom of a column while the rest of the text continues on the following page.
Leading Indent: The space between lines of text in a text block, one baseline to the next.
First Line Indent: Is when only the first text line of the entire text is indented. Usually to distinguish new paragraphs in writing.
Hanging Indent: This is when all of the text except the first text line is indented.
Sources: The Fundamentals of Typography; typeculture.com; Thinking with Type.