Evolution of Computer: References, https://www.wikipedia.org/

he Z3, an early computer built by German engineer Konrad Zuse working in complete isolation from developments elsewhere, uses 2,300 relays, performs floating point binary arithmetic, and has a 22-bit word length. The Z3 was used for aerodynamic calculations but was destroyed in a bombing raid on Berlin in late 1943.

Conceived by Harvard physics professor Howard Aiken, and designed and built by IBM, the Harvard Mark 1 is a room-sized, relay-based calculator. The machine had a fifty-foot long camshaft running the length of machine that synchronized the machine’s thousands of component parts and used 3,500 relays.

While many early digital computers were based on similar designs, such as the IAS and its copies, others are unique designs, like the CSIRAC. Built in Sydney, Australia by the Council of Scientific and Industrial Research for use in its Radio physics Laboratory in Sydney, CSIRAC was designed by British-born Trevor Pearcey, and used unusual 12-hole paper tape. It was transferred to the Department of Physics at the University of Melbourne in 1955 and remained in service until 1964.

The Alto is a groundbreaking computer with wide influence on the computer industry. It was based on a graphical user interface using windows, icons, and a mouse, and worked together with other Altos over a local area network. It could also share files and print out documents on an advanced Xerox laser printer. Applications were also highly innovative: a WYSISYG word processor known as “Bravo,” a paint program, a graphics editor, and email for example.

Apple Computer 1, also known later as the Apple I, or Apple-1, is a desktop computer released by the Apple Computer Company (now Apple Inc.) in 1976. The Apple I was Apple's first product, and to finance its creation, Jobs sold his only motorized means of transportation, a VW Microbus, for a few hundred dollars, and Wozniak sold his HP-65 calculator for $500; however, Wozniak said that Jobs planned to use his bicycle if necessary.

Sold complete with a main logic board, switching power supply, keyboard, case, manual, game paddles, and cassette tape containing the game Breakout, the Apple-II finds popularity far beyond the hobbyist community which made up Apple’s user community until then. When connected to a color television set, the Apple II produced brilliant color graphics for the time.

The MacBook Pro (sometimes abbreviated MBP) is a line of Macintosh portable computers introduced in January 2006 by Apple Inc. Replacing the PowerBook G4, the MacBook Pro was the second model to be announced during the Apple–Intel transition, after the iMac. It is the high-end model of the MacBook family and is currently available in 13- and 15-inch screen sizes. A 17-inch version was available between April 2006 and June 2012.