Fonts and Font Families

 

Chapter 19 - Graphics with GDI+
bySimon Robinsonet al.
Wrox Press 2002

  

We all think intuitively that we have a fairly good understanding of fonts; after all we look at them almost all the time. A font describes exactly how each letter should be displayed. Selection of the appropriate font and providing a reasonable variety of fonts within a document are important factors in improving readability.

Oddly, our intuitive understanding usually isn't quite correct. Most people, if asked to name a font, will say things like 'Arial' or 'Times New Roman' or 'Courier'. In fact, these are not fonts at all - they are font families . The font family tells you in generic terms the visual style of the text, and is a key factor in the overall appearance of your application. Most of us will have become used to recognizing the styles of the most common font families, even if we're not consciously aware of this.

An actual font would be something like Arial 9-point italic. In other words, the size and other modifications to the text are specified as well as the font family. These modifications might include whether it is bold, italic, underlined , or displayed in small caps or as a _subscript ; this is technically referred to the style , though in some ways the term is misleading since the visual appearance is determined as much by the font family.

The way the size of the text is measured is by specifying its height. The height is measured in points - a traditional unit, which represents 1/72 of an inch (0.351 mm). So letters in a 10-point font are roughly 1/7'' or 3.5 mm high. However, you won't get seven lines of 10 point text into one inch of vertical screen or paper space, because you need to allow for the spacing between the lines as well.

Strictly speaking, measuring the height isn't quite as simple as that, since there are several different heights that you need to consider. For example, there is the height of tall letters like the A or F (this is the measurement that we really mean when we talk about the height), the additional height occupied by any accents on letters like … or