Type is measured in terms of picas and points, which was developed by Simon Fournier in 1737, and perfected by Firmin Didot in 1785.

There are 12 points in a pica and approximately 6 picas in an inch (six picas are actually .9962 inches).

Type size is commonly measured in points beginning from 6 points & above.

In general anything less than 14 points is considered for body text and anything above is considered for headings and titles. Spaces between two lines are referred as the "leading" , because they use to create space between two lines using standardized strips of lead.

	If you are using sans-serif for body text, always keep heavy leading between two lines.
	Do not use capital letters unless it is necessary because the eye recognizes shapes more than letters and text in capitals has less shape than the text in upper and lowercase.
	Do not use reverse: Readers feel tiering when they read reversed text (white text on black background). Copy written in reverse gives poor response. Similarly text written over tints, textures or colored background becomes difficult to read.
	To bring attention of readers create contrast by using serif italic text, as eye does not find it difficult to read.
	Keep constant flow of fonts in the layout. Changing typefaces unnecessarily makes a layout look ugly. Similarly changing it within headlines makes it more confusing to the reader.
	Contiguous flow of text makes it hard to read, make it more meaningful by breaking it with the help of crossheads & subheads. Good Heading & titles makes’ user curious to read body text.