In an information recording method, information is recorded to semiconductor memory when at least a specified amount of free space exists in the semiconductor memory. Information is recorded to magnetic memory when the free space in the semiconductor memory is insufficient but at least a specified amount of free space exists in the magnetic memory. Information is recorded to optical memory when the free space in both the semiconductor memory and the magnetic memory is insufficient. When retrieving recorded information, an access count is incremented, and information with a comparatively high access count is moved to the semiconductor memory, while information with a comparatively low access count is moved to the optical memory. Information is thus recorded to a recording medium suitably selected from among semiconductor memory, magnetic memory, and optical memory, thereby making effective use of each memory type.