Dr James Sumner, lecturer in the history of technology at the University of Manchester, regards the development of The Baby as a milestone.
"It is the first machine that practically worked in the world using what is called the stored program," he says.
The prototype machine paved the way for commercial computers and was technically the first computer bought and sold, even though, the bill, made out in February 1951, was sent to the University of Manchester.
Dr Sumner says the developments since then have been "astonishing". According to his calculations, the prototype machine that first ran in Manchester on 21 June 1948 could store 1024 bits of information, each "bit" being a zero or one.
In contrast, a smartphone today might have 64 gigabytes of storage, which is 500 million times as much.
The 1948 machine was fast for its time, working at a rate of roughly 1,000 instructions per second.
Yet a modern processor for a laptop or tablet might reach 20 or 30 million times this speed, says Dr Sumner, and the instructions involved would be much more complicated.
The Baby machine was made up of a series of equipment racks running over five metres along the length of the room and weighed about a tonne.
Using the same space today it is possible to build massively powerful supercomputing machines, such as Manchester's SpiNNaker project, which is designed for simulating brain functions.