Method of operating a ferromagnetic thin-film based digital memory, having a substrate with a plurality of bit structures supported thereon and separated from one another by spacer material (11, 20, 22) therebetween, and that are electrically interconnected with information storage and retrieval circuitry (21; 21,23; 25-27, 29 and n>29: 25'-27', 29' and n>29'), said bit structures (19; 19') each comprising: a first magnetic material film (12, 12', 13', 13", 13'") in which a characteristic magnetic property is substantially maintained below a first critical temperature above which such magnetic property is not maintained and each having a first interconnection structure providing electrical contact thereto positioned against a first contact surface thereof and also between said first contact surface and said substrate, a second magnetic material film (17', 17", 17'", 18, 18') is provided in which a characteristic magnetic property is substantially maintained below a second critical temperature above which such magnetic property is not maintained, and with said second magnetic material film being separated from said first magnetic material film by at least one intermediate layer (14; 14, 15, 16) of a nonmagnetic material having two major surfaces on opposite sides thereof, said bit structures each having said first contact surface thereof substantially parallel to said intermediate layer major surfaces; and a plurality of word line structures (23, 23'; 21,23 23") each having a pair of word line end terminal regions adapted to conduct electrical current in at least one direction therethrough, each of said pairs of word line end terminal regions having an electrical conductor (23; 21, 23) electrically connected therebetween which is located on an opposite side of said intermediate layer of a corresponding one of said bit structures from said first interconnection structure providing electrical contact thereto, said method of operating being characterized in that it comprises: - drawing an electrical current selectively through each said bit structures and said first interconnection structure such that it causes heating of each said bit structures for reaching a temperature of at least one of said first and second magnetic material films that is approximately equal to its corresponding one of said first and second critical temperatures; and - isolating thermally at least an adjacent structure of each said bit structures. a first magnetic material film (12, 12', 13', 13", 13'") in which a characteristic magnetic property is substantially maintained below a first critical temperature above which such magnetic property is not maintained and each having a first interconnection structure providing electrical contact thereto positioned against a first contact surface thereof and also between said first contact surface and said substrate, a second magnetic material film (17', 17", 17'", 18, 18') is provided in which a characteristic magnetic property is substantially maintained below a second critical temperature above which such magnetic property is not maintained, and with said second magnetic material film being separated from said first magnetic material film by at least one intermediate layer (14; 14, 15, 16) of a nonmagnetic material having two major surfaces on opposite sides thereof, said bit structures each having said first contact surface thereof substantially parallel to said intermediate layer major surfaces; and a plurality of word line structures (23, 23'; 21,23 23") each having a pair of word line end terminal regions adapted to conduct electrical current in at least one direction therethrough, each of said pairs of word line end terminal regions having an electrical conductor (23; 21, 23) electrically connected therebetween which is located on an opposite side of said intermediate layer of a corresponding one of said bit structures from said first interconnection structure providing electrical contact thereto, - drawing an electrical current selectively through each said bit structures and said first interconnection structure such that it causes heating of each said bit structures for reaching a temperature of at least one of said first and second magnetic material films that is approximately equal to its corresponding one of said first and second critical temperatures; and - isolating thermally at least an adjacent structure of each said bit structures.