Abstract: Apparatus is provided using as an integral portion thereof a confined array (such as a lattice) of interactive elements, the interactions among which are largely determinative of the positions of the interactive elements since there is a minimum of position determining structure for the elements within the area of confinement. Magnetic elements are suitable interactive elements, and in particular embodiments are shown using magnetic bubble domains. Structure is provided to form lattice arrays of interactive elements, to confine the lattice arrays, and to access elements outside and within the lattice array. In addition, various structures are provided to code the interactive elements for storage of information, and reading devices are provided to detect the information state of the interactive elements when these elements are coded. Various types of lattices and interactive elements can be used.