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An early systematic use of medial capitals is the standard notation for chemical formulae, such as NaCl, that has been widely used since the 19th century.

In the 1970s, medial capitals became an alternative ( and often standard ) identifier naming convention for several programming languages.

Since the 1980s, following the popularization of computer technology, it has become fashionable in marketing for names of products and companies, and for 1990s online video games where players use pseudonyms ( when spaces were not allowed ).

However, medial capitals are rarely used in formal written English and most style guides recommend against their use.