Web Typography - Type Face and Size

16pt Times New Roman

16px Times New Roman

14pt Times New Roman

14px Times New Roman

12pt Times New Roman

12px Times New Roman

Windows and Macintosh have different screen resolutions. Windows are usually set at 96 pixels per inch (ppi) and Macintosh is 72 ppi. One inch width line in Windows is 96 pixels and on a Mac is 72 pixles creating a difference of 24 pixels.
In graphical terms one point is 1/72 of an inch. Therefore on a Macintosh, 10-point type is 10 pixels, but on a PC it is about 13 pixels.
The new browser IE5 and NN6 have resolved this situation. The problems lies with the older browser which will show inconsistencies in font sizes. Additional Font information at: Apple Font Sizing

Typeface can be classified into five-seven types: serif, sans serif, decorative, oldstyle, modern, transitional. Type on the web usally display either Serif or Sans Serif. The purpose of the typeface is to make text on a web page easy to read. Readability is the goal of all web designers.

Serif Fonts
Bookman Oldstyle
Times New Roman
Courier New
Garamond
Lucinda Bright
Serif Fonts are characterized by the decorative edges or feet and best used for textbooks and newspapers articles.
Sans Serif Fonts
Arial
Comic Sans MS
Futura
Helvetica
Verdana
Sans means without therefore Sans Serif refers to type face without the feet. Sans Serif type is best used for headlines, titles and the web.
Fancy Fonts
Lucida Calligraphy
Edwardian Script IT
The decorative typeface are used for their general appearance but make readability difficult.

More text attributes using Cascading Style Sheets Language in XHTML II
Web Content Accessibility Guide WCAG 1.0 of the W3C Web Accessibility Initiative  www.w3.org/WAI