In order to render text, the Amiga needs to have a graphical representation for each symbol or text character. These individual images are known as glyphs. The Amiga gets each glyph from a font in the system font list. At present, the fonts in the system list contain a bitmap of a specific point size for all the characters and symbols of the font. Fonts are broken up into different font families. For example, the Amiga's Topaz is a font family. Each font family shares a basic look but can have a variety of styles and point sizes. The style of a font refers to a minor alteration in the way the plain version of the font's characters are rendered. Currently, the Amiga supports three font styles: bold, italics and underline (the font's style may also be considered plain when it does not have any of these styles). Although these styles can be inherent to a font, they are normally added algorithmically as text is rendered. On the Amiga, the point size of a font normally refers to the height of the font in pixels. For example, Topaz-8 is 8 pixels high. Because the size of Amiga pixels varies between display modes, the appearance of a font will also vary between display modes. Future versions of the Amiga OS may measure font size in other units. For example, the standard point in the PostScript page description language normally refers to a point as being a square dot that is 1/72 of an inch on a side. Using a standard measuring unit such as the PostScript point makes it possible to create a WYSIWYG (What You See Is What You Get) display that exactly matches printer or other device output. When the Amiga first starts up, the only fonts in the system font list are Topaz-8 and Topaz-9, both of which are in ROM. Any other fonts must be loaded from disk or generated somehow. In Amiga operating systems prior to Release 2, additional fonts have to be loaded from disk (usually from the FONTS: directory) using the diskfont.library. For each font size of each font family there is a corresponding bitmap file on disk. If there is no bitmap on disk or in ROM for a specific font size, that font size is not available (if the operating system is 1.3 or earlier). system fonts in release 2