## The History of Computing

- Abacus
- Analog Computers
- Digital Computers
- Electronic Computers
- Computer Speed

## The First Abacus

The **Babylonian Abacus** was developed to **Reduce the Time** to perform calculations.

As stated in the previous chapter, we believe that the Babylonians invented complex counting.

The period 2700–2300 BC probably saw the first appearance of an abacus, a table of successive columns which defined the orders of a **60 digits** number system.

## Abacus 2.0

The **Roman Abacus** used 10 digits Roman numbers to **Reduce the Time** to perform calculations:

Image: 1911 Encyclopedia Britannica (public domain).

The Romans developed the Roman Abacus, a portable, base-10 version of earlier abacuses used by the Babylonians.

This was the worlds first handheld computer. Used by Roman engineers, merchants and tax collectors.

## Analog Computers

**The Difference Engine** (Charles Babbage 1822) was a mechanical machine designed to **Reduce the Time** to calculate complex mathematical functions.

**The Analytical Engine** (Charles Babbage 1833) was a mechanical machine designed with modern computer elements like arithmetic, logic, and memory.

Both these “computers” used 10 digit (decimal) mechanical cogwheels to perform mathematical calculations:

(Charles Babbage’s Analytical Engine. Science Museum. London)

## Digital Computers

Digital Computers use 0/1 switches to perform calculations. They operate on **binary** values like 11100110 in contrast to **analog** values like 230.

Try It Yourself:

+

=

The first Electric Digital Computer was designed and built by Konrad Zuse in Germany (1941).

It used 2600 electrical relays as 0/1 switches. The clock speed was about 5 Hz.

Replica of the Zuse Z3. Deutsches Museum. Munich.

## Electronic Computers

**First generation Computers** (1945-1950) used vacuum tubes as binary switches.

Vacuum tubes are much faster than electrical relays.

The clock speed of these computers was between 500 KHz and 1 Mhz.

## Second Generation Computers

**Second generation Computers** (1950-1960) used transistors as binary 0/1 switches.

Transistors are much faster than vacuum tubes.

## Third Generation Computers

**Third generation Computers** (1960) used integrated circuits as binary switches.

Integrated circuits are much faster than transistors.

## Computer Speed

The first electrical computer could do 5 instructions per second.

The first electronic computer did 5000 instructions per second.

The first PC did 5 million instructions per second.

AMD was the first PC to reach 1 billion instructions per second.

Today, IPhone 12 can do 11 billion instructions per second.

Year | Computer | Instructions per Second | Bits per Instruction |
---|---|---|---|

1941 | Z3 | 5 | 4 |

1945 | ENIAC | 5.000 | 8 |

1981 | IBM PC | 5.000.000 | 16 |

1995 | Intel Pentium PC | 100.000.000 | 32 |

2000 | AMD PC | 1.000.000.000 | 64 |

2020 | 10.000.000.000 | 128 |

## When Did it Start? Where Will it End?

From the history above you can extract:

- Computers were designed to do calculations
- Charles Babbage created the first mechanical computer
- The first digital computers used electromechanical switches
- Vacuum tubes are much faster than electromechanical switches
- Transistors are much faster than vacuum tubes
- Integrated circuits are much faster than transistors
- Tomorrow’s computes will be faster than the human brain?

*“Computers are useless because they can only give you answers.”*

Pablo Picasso

## Smarter Than Humans?

If we believe in Moores Law:

In 2020, computers have the capacity of a mouse brain.

In 2030, computers might have the capacity of a human brain:

Source: Ray Kurzweil