Abstract: An information processor capable of easily dealing with addition or alteration of a format engine is provided. The information processor includes format engine management means and operation control means. The format engine managing means pre-defines common states which define operating states of each format engine in a representation common to all the format engines, and manages an operation of each format engine. The operation control means is provided in correspondence with each format engine, and pre-defines a correspondence between the common states and individual states which define the operating states of each format engine in a representation different for each format engine, and controls operations of the format engines such that each format engine is in an arbitrary individual state.