A The New Font Selection Scheme
When TEX and LATEX were invented, the fonts available for them were very limited in number. For this reason, the original LATEX had an inflexible system of defining the fonts that were to be used, since it was not obvious that one might want to change them. The association between the high-level font commands such as
\bf and the external font name that is ultimately selected was rigidly fixed internally.
Today there are many additional fonts available, some of which should be used alongside the standard CM fonts and others that should replace them altogether. For example, the Cyrillic fonts of Section 15.4.2 should be added parallel to the Latin fonts, but to make them operate automatically under the ...