 In the UK, three projects were then underway to develop a stored program computer (in Cambridge, the NPL and Manchester) and the main technical hurdle was the memory technology.In order to test the cathode ray tube memory designed by FC Williams when it was constructed, Kilburn and Tootill designed an elementary computer, known as the "Manchester Baby".The computer could store 32 instructions or numbers using a single Cathode Ray Tube (CRT).