Herman Jan Couwenberg, best known as the cartoonist Djanko, graduated as a jurist in the mid 1980s. He quickly turned to cartooning and has published his work in a great variety of publications since. His simple yet effective style gives the reader a humorous look on life.
He is a regular contributor to the comics magazine Zone 5300 and his work has also appeared in Het Vrije Volk, Rotterdams Dagblad, AD, VPRO Gids, the FNV magazines, Intermediair PW, Esta and many more. He has makes comic strips like 'Hugo & Bob' and 'Zorg & Zo'.
He has also drawn for national and local government agencies and is for hire as a stand-up cartoonist during seminars, meetings and conferences.His cartoons have been collected in books like 'Hoera ik werk' (1996) and 'Zinloos Geluk' (2005).