Chess composers usually specialize in a particular genre, e.g. endgame studies, twomovers, threemovers, moremovers, helpmates, selfmates, fairy problems, or retrograde analysis.
The WFCC (World Federation for Chess Composition), formerly known as PCCC, is a branch of FIDE regulating the awarding of titles such as International Grandmaster, International master, Master FIDE and International Judge for chess composition.
Composition school in chess composition is a particular style of creating chess problems, putting emphasis on different aspects of the problem contents and attracting the interest of an important number of chess composers.
The best-known composition schools, as they evolved historically, are: Many chess problems are clearly attributable to a specific one of these schools, but there are many problems that might be attributed to none of these or to more than one of them.
Today, many chess composers regularly do work in the area of multiple schools.