Computers actually started for the need of counting and making other calculations, realizing that limitation of having only those ten fingers and toes used to make such computations. Based on my research, this started of with the so called ABACUS, an apparatus that used a series of movable beads or rocks. It's a manual installation, that is purposely made for livestock and trade.
Then came Blaise Pascal's invention, the adding machine, that's initially built for commerce and not for science.
Next was Charles Babbage's idea for a computer that would not only calculate, but also print mathematical tables. This uses punch cards that can use previous calculations to new ones. Then another mathematician, Ada Byron Lovelace got inspired of Charles Babbage's works. She realized that Analytical Machines are possible to produce graphics and music. She was then known for writing the world’s first computer program. Then the United States Department of Defense named a computer language in her honor in 1979. Afterwards, several computer inventions followed those earlier ideas.
First Generation (1940-1956) Vacuum Tube
The first computers used vacuum tubes for circuitry and magnetic drums for memory, consuming a lot of electricity, causing it to have several malfunctions. The first electronic computer ENIAC(Electronic Numerical Integrator and Computer), the brain, came out in 1946. In 1951, UNIVAC was the first computer used by U.S. government, U.S.A. Then IBM computers were sold in U.S.A., next to Apple computers.
Second Generation (1956-1963) Transistors
Transistors replaced vacuum tubes and were far of superior to it. Computers become smaller, faster, cheaper, more energy-efficient and more reliable than the earlier generation of computers. These used languages that let programmers specify instructions in words. This generation still relied on punched cards for input and printouts for output. The first computers of this generation were developed for the atomic energy industry.
Third Generation (1964-1971) Integrated Circuits
Now this generation deals with keyboards and monitors and interfaced with an operating system. Integrated circuit was the special indication of the third generation of computers. I found out that transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers.Now computer turned accessible to users because it was smaller and cheaper.
Fourth Generation (1971-Present) Microprocessors
This is the start of shrinking of all those large inventions that could fill up a room in the first generation into silicon chips. This is where Apple introduced Macintosh to consumers in 1984 . Then IBM mainframes were used by government and corporations which later on made open for the IBM PC consumers. This generation actually was more applicable to a lot of users that led to the realization of network and internet. Fourth generation computers also includes development of GUIs, the mouse and handheld devices.
Fifth Generation (Present and Beyond) Artificial Intelligence
Fifth generation computing devices, are based on artificial intelligence, which covers that a computer will solve problems in exactly the way they are programmed to, regardless of efficiency nor alternative solutions nor possible shortcuts nor possible errors in the code. Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come according to my research. These are are still in development, though some are already into process of applications.
And based on Wikipedia, Quantum computer, Chemical computer, DNA computing, Optical computer, Spintronics based computer are still included in the theoretical or experimental computing hardware.
In conclusion to that, we can't actually determine who invented the computer, considering that a lot of mathematicians and inventors contributed to the acceleration of computer generation. And though computers at present are far better than their predecessors, technology of today wouldn't reach that far if not for our earlier inventors that combined discoveries to create such a master of improvement to the society.
references:
http://www.webopedia.com
http://www.wikipedia.com