The font style is generally controlled with the
set font command. To temporarily override the font in a string of text, use the back quote character (`). A back quote followed by a digit selects that font number for the remainder of the string. It is also possible to use the back quote to change the position of the text, to draw a string above or below the base line for subscripts or superscripts. A back quote followed by the letter a (`a) will draw the subsequent text in the string as a superscript (above normal). A back quote followed by the letter b (`b) will draw the subsequent text in the string as a subscript (below normal). A back quote followed by the letter n (`n) will draw the subsequent text in the string in a normal position, to undo the effects of `a or `b. The use of the back quote to override the font works with the draw string command, contour labels, titles, axis labels, etc.
draw string 1.5 1.25 `1use font 2 to `2emphasize `1a particular word draw string 1.5 2.25 `0use font 3 for `3greek `0letters draw string 1.5 3.25 `3p`0r`a2`n = area of a circle draw string 1.5 4.25 label temperatures in `3.`0C or `3.`0F