|Charles Babbage's Difference Engine|
|Intel's 4004 [source: cpu-zone.com]|
|Frederico Faggin [source: bbci]|
|The MCM/70 [source: wikimedia]|
|The MITS Altair 8800|
Using the Altair was an experience that most people will never have to endure. Commands were fed into the computer by configuring the switches on the front panel so they corresponded with whichever opcode (from a list of instructions the CPU can carry out) the user wanted. Some data would then usually be entered and so on. You would eventually receive visual output in the form of an array of LEDs on the front panel and you would have to attach a terminal if you wanted to view output on a screen. Altair BASIC, the computer's programming language, was written by a couple of guys called Bill Gates and Paul Allen from a company called Micro-Soft.
Anyway, the Altair sold many more than was expected, and basically kicked off the microcomputer revolution from which all others followed. Being able to write and read machine language in binary, however, restricted these 'first generation' PCs from achieving wide popularity, limiting their audience largely to hobbyists and scientists. In the following months, rapid advances in technology, along with low component prices, made it possible for the next generation to introduce a keyboard and a monitor for input and output of human language. BASIC found itself as the standard for programming, and computers could now plug into a regular TV.
|An original Apple I [source: wb.com]|
1977 was the year the personal computer really came into being and, depending on who you ask, one of the following three computers has a claim as the first genuine PC:
The Apple ][
The first Apple was not a 'proper' computer. It didn't have a case, a keyboard or a power supply. The second Apple did. Most importantly, where hobbyists had been the previous market of small computer makers, the Apple II was aimed at businesses and home users. It could be connected to a standard TV, included a pair of paddles for gaming and could display colour, which was unheard of among consumer-grade computers. The inclusion of Apple's version of BASIC in the computer allowed users to write their own programs without having to buy any additional software, and a cassette deck could be used to store data. The Apple ][ was also the first computer that had a 'killer app' i.e. a piece of software that was so useful you bought the computer just to have it. That software was Visicalc, the first digital spreadsheet. It caused an explosion of sales: between September 1977 and September 1980, this one computer took Apple's sales figures from $775,000 to $118 million, and the rest is history.
The Commodore PET
The Tandy TRS-80