There are many more examples. Note that measuring each of these properties will not alter the basic nature of the substance. Examples of chemical properties are: heat of combustion, reactivity with water, PH, and electromotive force.
Mathematical fonts. In mathematical mode you can change the typefaces of the fonts when needed. For instance, it's customary to represent real numbers with a blackboard bold font, or topological spaces with calligraphic font. This article shows several fonts in math mode.
Although there are many classifications for fonts, the one that matters in web design is the generic font family names as defined in the W3C CSS specification: serif, sans-serif, cursive, fantasy, and monospace. The W3C system is terse, but it is how we actually refer to the fonts in our CSS code.