X Idnentification

xlsfonts lists the currently loaded fonts.

bash> xlsfonts ... -adobe-courier-bold-o-normal--0-0-75-75-m-0-iso8859-1 ... -adobe-new century schoolbook-medium-i-normal--12-120-75-75-p-70-iso8859-14 ... -urw-nimbus roman no9 l-medium-i-normal--0-0-0-0-p-0-iso10646-1 ...

X identifies fonts by a hyphen-separated string.

Foundry
Font Publisher
Family
General Font Identification
Weight
bold/medium/...
Slant
roman/italic/...
...
Pixelsize
Bitarray Dimensions
Pointsize
Linear Dimensions
...
XResolution-YResolution
Aspect Ratio - Pixels/Inch
...
Registry-Encoding
Publisher and Identification