The motive of this article is to give you clear & concise understanding of modern computing, its evolution, and basic principles of it.

It all started in 1940–1945, when the United States and Britain worked independently on creating computers to gain an advantage during the war. By 1951, there was a commercial computer on the market. Information could now be processed and manipulated automatically. Here’s the story of how it all happened.

In 1942, the first all-electronic digital computer, Atanasoff Berry Computer (ABC) was constructed. It was a breakthrough since it used electronic vacuum tubes to perform calculations, rather than wheels or mechanical switches as previous computers did. However, the computer was not re-programmable or general purpose at all.

The successor to ABC, was ENIAC, which was the first programmable digital computer. It was a 15-meter-long machine that weighed about 30 tons. The worst part? There were 17,500 delicate, prone-to-breaking vacuum tubes, if any one of the broke, the whole machine halted working.

After the war and the ENIAC project, Mauchly and Eckert decided to use this new computer technology to make life easier. In March of 1951, after six years of work, the university pair sold the first general-purpose computer to the United States Census Bureau: UNIVAC.
After vacuum tubes, it was time for something new. In the 1930s, Bell Labs’ director of research (Bell Labs was the research branch of AT&T — the company founded by Graham Bell), Mervin Kelly, recognized that a better device was needed for the telephone business to continue to grow. He had a feeling that the solution might lie in semiconductors. This marks the birth of transistor. We will get back to that later.

Origins of internet: In 1958, American Telephone & Telegraph, the company mentioned above as AT&T & now global leader in internet service providers, came up with digital version of modem which could provide internet with speeds up to 110 bits a second. With that speed, an average webpage (500 KB) would have taken fifteen hours to load. Imagine clicking on a video, then coming back to watch it two and a half months later.
In the same year (1958), the world saw the first graphical video game called ‘Tennis for Two’. The controls were simple — a twistable knob to adjust the angle at which the player was about to hit the ball, and a push button to fire the shot. The game was so appreciated that it took very less time to get into the mainstream.

Transistors proved to be much efficient than vacuum tubes, being useful in radios, but their use in functioning computers was limited. If enough transistors could be packed into a sufficiently small space, there could be serious computing power. This introduces the concept of Integrated Circuit. Our modern CPUs use Integrated Circuits, packing billions of tiny transistors. In the starting days, William Shockley (the founding father of transistor) formed a lab called ‘Shockley Semiconductor Lab’. The Lab brought together a pool of talent that would become the foundation of what we now know as Silicon Valley. Robert Noyce & Gordon Moore were one of them. Due to Shockley’s paranoid nature, these eight soon left Shockley’s Lab and pioneered a new firm called ‘Fairchild Semiconductor’ now known as Intel. These people later got their title as ‘The Traitorous Eight’.

Intel soon created new chip called ‘Intel 4004’ chip, packing in 2000 transistors. 70s saw production of mobile phones and video games were in mainstream. In 1975, concept of personal computing begun to emerge.
Among the major players in computer market were Apple & IBM at that time. Since Apple had their own operating system, IBM needed one, for that purpose, IBM approached renowned computer scientist Gary Kildall (the man who could have been Bill Gates) to create an operating system for them. On Bill Gates’ advice, IBM team paid a visit to Gary’s house. Despite of Gates’ hint “Treat them right; they’re important guys!”, Gary didn’t take it seriously, so the deal wasn’t successful. Then the IBM approached Bill Gates and he didn’t miss the chance. Soon Gates came up with DOS and founded Microsoft.
Martin Cooper shocked the world with the very first mobile phone, the Motorola DynaTAC x 8000, in 1984. Apart from that, web explosion was observed. It began in August 1991 with one website, The World Wide Web Project. By 1992, there were ten websites. Initially, there was no commerce allowed on the internet, but this was overturned by Congress in 1992. The following year, CERN made the web free and public. By that end of the year, there were already 14 million internet users worldwide, but only 130 websites.
Sony launched their first Playstation in 1994 and launch of Windows 95 followed in 19995.

Beginning of 21st century brought mp3 players in the mainstream, thanks to Apple’s iPod. By 2002, social media started to rise with the launch of: Friendster (2002), Myspace (2004) followed by Facebook in the same year. YouTube connected the world through videos in 2005 and saw an exceptional growth. Smartphone era begun in 2007 with iPhone. After the success of iPhone, ‘The App Boom’ was observed in 2008, the Android phones were originated in the same year.
Till then, the CPUs became so powerful that the power of whole US-Spread ENIACs could be fit into palm of the hand. Data could be processed at phenomenal speeds, this made computer scientists to shift their focus towards Artificial Intelligence. Physical limitations regarding transistor size brought new concept of Quantum Computing.

Today, computers have become integral part of our lives, we are deeply involved in AI & ML and moving towards Internet of Things.
This was the brief chain of innovations that formed the world that we see & observe today, lot much to come yet…