Update

history.md

@@ -50,8 +50,12 @@ In 1931 [Kurt Gödel](kurt_godel.md), a genius mathematician and logician from A
 
 In 1938 [Konrad Zuse](konrad_zuse.md), a German engineer, constructed **[Z1](z1.md), the first working electric mechanical [digital](digital.md) partially programmable computer** in his parents' house. It weighted about a ton and wasn't very reliable, but brought huge innovation nevertheless. It was programmed with punched film tapes, however programming was limited, it was NOT [Turing complete](turing_complete.md) and there were only 8 instructions. Z1 ran on a frequency of 1 to 4 Hz and most operations took several clock cycles. It had a 16 word memory and worked with [floating point](float.md) numbers. The original computer was destroyed during the war but it was rebuilt and nowadays can be seen in a Berlin museum.
 
+In hacker culture the period between 1943 (start of building of the [ENIAC](eniac.md) computer) to about 1955-1960 is known as the **Stone Age of computers** -- as the [Jargon File](jargon_file.md) puts it, the age when electromechanical [dinosaurs](dinosaur.md) ruled the Earth.
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 In 1945 the construction of **the first electronic digital fully programmable computer** was completed at University of Pennsylvania as the US Army project. It was named **[ENIAC](eniac.md)** (Electronic Numerical Integrator and Computer). It used 18000 vacuum tubes and 15000 relays, weighted 27 tons and ran on the frequency of 5 KHz. [Punch cards](punch_card.md) were used to program the computer in its machine language; it was [Turing complete](turing_complete.md), i.e. allowed using branches and loops. ENIAC worked with signed ten digit decimal numbers.
 
+Among hackers the period between 1961 to 1971 is known as the **Iron Age of computers**. The period spans time since the first minicomputer ([PDP1](pdp1.md)) to the first microprocessor ([Intel 4004](intel4004.md)). This would be follow by so called *elder days*.
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 On July 20 1969 **first men landed on the Moon** (Neil Armstrong and Edwin Aldrin) during the USA Apollo 11 mission. This tremendous achievement is very much attributed to the cold war in which USA and Soviet Union raced in space exploration. The landing was achieved with the help of a relatively simple on-board computer: Apollo Guidance Computer clocked at 2 MHz, had 4 KiB of [RAM](ram.md) and about 70 KB [ROM](rom.md). The assembly source code of its software is nowadays available online.
 
 Shortly after, on 29 October 1969, another historical event would happen that could be seen as the start of perhaps the greatest technological revolution yet, the **start of the [Internet](internet.md)**. The first letter, "L", was sent over a long distance via **[ARPANET](arpanet.md)**, a new experimental computer [packet switching](packet_switching.md) network without a central node developed by US defense department (they intended to send "LOGIN" but the system crashed). The network would start to grow and gain new nodes, at first mostly universities. The network would become the Internet.