Fonts that fall into the Serif category have unconnected short lines or curves called "serifs" at the end of its letters. It is one of the easiest fonts to read as the small short lines guide the reader to the next character and facilitate the movement of the eyes across the letters. Examples of popularly used Serif fonts are Times New Roman and Garamond.
Sans means 'without' in French--as such, Sans Serif fonts are fonts that do not contain the short lines or curves that appear at the end of characters. Since Sans Serif fonts are more difficult to read compared to Serif, they are reserved for use as headings, sub-headings, titles or captions. Arial, Verdana and Helevetica are just among the many fonts that belong to the Sans Serif category.
As its name implies, Script fonts are fonts that are interconneted--much like handwritten script. Aside from looking handwritten, other Script fonts also look like they were written with a calligraphy pen or brush.This type of font is used in art, cover designs, greeting cards or invitations, but is rarely used for instructional materials or textbooks. Examples of Script fonts include Park Avenue and French Script.