A compendium (pl.: compendia or compendiums) is a comprehensive collection of information and analysis pertaining to a body of knowledge. A compendium may concisely summarize a larger work. In most cases, the body of knowledge will concern a specific field of human interest or endeavour (for example: hydrogeology, logology, ichthyology, phytosociology or myrmecology), while a general encyclopedia can be referred to as a compendium of all human knowledge. The word compendium arrives from the Latin word compeneri, meaning "to weigh together or balance". The 21st century has seen the rise of democratized, online compendia in various fields. Source: Wikipedia (en)