For almost all units of measurement Text Control uses *twips*. *Twip* is
a fabricated word meaning *twentieth of a point*. A point which is a unit of measurement for type, is
approximately 1/72 inch but often assumed in graphics systems sach as Windows GDI to be exactly 1/72 inch. A
*twip* is 1/20 point and hence 1/1440 inch.

Type size is expressed in units called *points*. A point is very close to 1/72 inch, so
close that it is often defined as exactly 1/72 inch. The point size indicates the height of the characters. For
instance, when we speak of 12-point type, we are referring to characters that are 12/72 inch high from the top
of the ascenders to the bottom of the descenders.