Formats for Text in Graphics

BaseStyle->valuean option for the text style in a graphic
FormatType->valuean option for the text format type in a graphic

Specifying formats for text in graphics.

Here is a plot with default settings for all formats:
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Here is the same plot, but now using a 12point bold font:
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This uses StandardForm rather than TraditionalForm:
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This tells the Wolfram Language what default text style to use for all subsequent plots:
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Now all the text is in 14point Times font:
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"style"a named style in your current stylesheet
FontSize->nthe size of font to use in printers points
FontSlant->"Italic"use an italic font
FontWeight->"Bold"use a bold font
FontFamily->"name"specify the name of the font family to use (e.g. "Times", "Courier", "Helvetica")

Typical elements used in the setting for BaseStyle.

If you use the standard notebook front end for the Wolfram Language, then you can set BaseStyle to be the name of a style defined in your current notebook's stylesheet. You can also explicitly specify how text should be formatted by using options such as FontSize and FontFamily. Note that FontSize gives the absolute size of the font to use, measured in units of printers points, with one point being inches. If you resize a plot whose font size is specified as a number, the text in it will not by default change size: to get text of a different size you must explicitly specify a new value for the FontSize option. If you resize a plot whose font size is specified as a scaled quantity, the font will scale as the plot is resized. With FontSize->Scaled[s], the effective font size will be s scaled units in the plot.

Now all the text resizes as the plot is resized:
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Style[expr,"style"]output expr in the specified style
Style[expr,options]output expr using the specified font and style options
StandardForm[expr]output expr in StandardForm

Changing the formats of individual pieces of output.

This outputs the plot label using the section heading style in your current notebook:
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This uses the section heading style, but modified to be in italics:
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This produces StandardForm output, with a 12point font:
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You should realize that the ability to refer to styles such as "Section" depends on using the standard Wolfram Language notebook front end. Even if you are just using a textbased interface to the Wolfram Language, however, you can still specify formatting of text in graphics using options such as FontSize. The complete collection of options that you can use is given in "Text and Font Options".