English: Tree showing evolution of computers used by US Army from the ENIAC.

ELECTRONIC COMPUTERS WITHIN THE ORDNANCE CORPS
CHAPTER VII -- THE COMPUTER TREE
The computer tree shows the evolution of electronic digital computers. The automatic computing and data processing industry is a direct outgrowth of research, sponsored by the U.S. Army Ordnance Corps, which produced the ENIAC, the world's first electronic digital computer. This industry has grown to a multi-billion dollar activity that has penetrated every profession and trade in government, business, industry, and education.

In the accompanying graphical representation of the computer tree the trunk rests on the ENIAC. The serial computers, represented by EDVAC, and the parallel computers, represented by the ORDVAC, are shown as separate limbs. This separation tends to distinguish the business computers on the left limb from the scientific computers on the right limb. The computers which were developed specifically to meet military needs are shown on the center limb. Manufacturers have entered the electronic computer field at different times, shown as various branches. Only university and government sponsored computers are shown along the limbs. The radial distance from the ENIAC is an approximate indication of the year each computer was developed, constructed, or placed in operation.