4th Generation Computers: Microprocessor, Rise of Apple and Microsoft

1971 - Present


With the creation of Intel's 4004 4-bit microprocessor in 1971, computers could perform multiple actions at once. It was able to combine millions of transistors along with other components of the computer onto a single chip making what used to take up part of a wall now only take a corner in your living room. This made computers reliable, faster, and more affordable. In 1972 Intel released a new 8-bit processor the 8008, with technology ever growing and hardware becoming cheaper and more efficient computers made their way to people's homes. This new technology a market opened up with multiple companies such as Apple and IBM creating computer hardware for the everyday man to understand, use, and own.

Alot of software was created during this time, most notably is Bill Gate's Microsoft Windows Operating System created in 1985 as well as the C++ programming language also created 1985.
Some of the more notable computers during this time are the Altair 880, Apple's Lisa and Apple Macintosh.

The Altair 880 released in 1975 could be considered the first Personal computer, but it lacked almost any kind of interface and was more of a hobby kit to learn about computers. 

Apple's Lisa released in 1983 was the first home computer to use a graphical interface. Instead of typing out code like before to talk with the computer, the graphical interface represented what you wanted to do with the computer. This would be where the idea of a 'desktop' and 'folders' and 'files' on a computer is born. Instead of typing out lines to move, open or delete folders and files, the operator can now see the files and folders on the computer screen much like how we do on today's computers. Even with this revolutionary interface Lisa sold poorly since its price tag was so high, even still Lisa lead the way in how we interact with our computers today. 

Apple's Macintosh released in 1984 followed Lisa's footsteps in having a graphical interface but also improved its overall efficiency and lowered cost to be able to sell well. With a much cheaper price tag Apple's Macintosh made it's way into peoples homes and established itself as one of the leading computer companies. One of the first right steps toward a computer system we still use today. 


sources cited:
http://library.thinkquest.org/C0115420/Cyber-club%20800x600/History/3rd%20Generation%20Computers%20%281964-1971%29.htm
http://library.thinkquest.org/C0125787/thigen.htm
http://www.webopedia.com/DidYouKnow/Hardware_Software/2002/FiveGenerations.asp

 

3rd Generation Computers: Integrated Circuits

1965 - 1970

Even though transistor technology made computers smaller and cheaper, transistors still managed to overheat and cause damage to parts of the computer. To solve this problem the Integrated Circuit was invented by Jack Kilby of Texas Instruments.

The Integrated Circuit shrunk the multiple transistors and placed them onto a small silicon disk made of quartz which prevented overheating. The integrated circuit also had small silicon chips, or semiconductors, which markedly increased efficiency and speed of the computer.
This was one of the first steps toward the modern day microprocessors.

 These 3rd generation computers were also the first computers to use keyboards and monitors as input and have an operating interface. Because of this, machine language such as punchcards and tape were no longer needed to talk to the machine. 3rd generation operating systems allowed for computers to run multiple programs at a time while also monitoring the computer's memory. Simplifying operation and lowering prices meant that computers now appealed to a broader audience and was much more affordable than ever before.



sources cited:
http://library.thinkquest.org/C0125787/firgen.htm
http://www.webopedia.com/DidYouKnow/Hardware_Software/2002/FiveGenerations.asp

2nd Generation Computers: Transistors

1959 - 1964

Replacing the vacuum tubes within the first generation were Transistors, a device that tells a circuit either to open or close and amplifies signals. Transistors were the forerunner of the modern day microprocessors we have today. Current day microprocessors house millions of tiny, microscopic transistors delivering markedly increased processing and computing power compared to the 2nd generation computers.

Due to the replacement of vacuum tubes with transistors the space and overall resources required for the computer to run were significantly reduced. Before transistors existed digital circuits were composed of vacuum tubes which would mean the ENIAC would take up an absurd amount of space such as whole rooms, take a lot of electricity to power and were more prone to overheating and failing. With the invention of the Transistor, computers would now only take up a part of a wall rather than a room, use less electricity, create less heat and cost less. The transistor increased overall efficiency while saving valuable resources.

2nd generation computers also moved forward in terms of input, during this time programming languages were in development so an operator can talk directly to the computer through software rather than physical input such as punch cards and tape. The memory within the computer was now saved onto a magnetic core rather than a magnetic drum, which was used during during the first generation of computers.

sources cited:
http://www.webopedia.com/DidYouKnow/Hardware_Software/2002/FiveGenerations.asp
http://library.thinkquest.org/C0125787/firgen.htm

1st Generation Computers: Inspirations and Vacuum Tubes

1941 - 1958

In 1936 Alan Turing created the Turing Machine, a kind of influence and precursor to modern day electrical computers.
Turing Machines are abstract computer models that perform logical operations in analog form. They are used to prove abstract theorems in computer science.
Within the Turing machine a line of cells or 'tape' and a single active cell or 'head' have different colors and states. The tape has a variation of colors and the head has a few different states. The way it is operated is that the machine follows a rule, it first looks at the color of the tape, then the state of the head, then it decides what the new state of the head should be, what color tape to write on and whether to move left or right. Since this was not a general all purpose computer it wasn't owned or used by the public, it was mainly used by scientists.

From the strife of World War 2 the first general purpose computer was born from a partnership between the U.S. Government and The University of Pennsylvania. The ENIAC or Electronic Numerical Integrator and Computer was created by John W. Mauchly and J. Presper Eckert. The same team also created the UNIVAC, short for Universal Automatic Computer which was meant for commercial use.

These first generation computers used vacuum tubes for circuitry and talked in machine language rather than a software. Meaning that in order to talk with the computer the operator needed to feed it punched cards or tape and the machine would respond by creating a print out. The memory of the computer was stored onto a magnetic drum.
These computers were often large and take up whole rooms, they could tackle one problem at a time meaning one would be at this computer for an extended amount of time and due to this they would heat up take up a lot of electricity. Making this computer expensive both hardware wise and resource wise.




sources cited:
http://www.wolframscience.com/prizes/tm23/turingmachine.html
http://www.webopedia.com/DidYouKnow/Hardware_Software/2002/FiveGenerations.asp
http://library.thinkquest.org/C0125787/firgen.htm