Computador

Computer
A computer is a programmable machine designed to automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily,allowing the computer to solve more than one kind of problem. An important class of computer operations on some computing platforms is the accepting of input from human operators and the output of resultsformatted for human consumption. The interface between the computer and the human operator is known as the user interface.
Conventionally a computer consists of some form of memory, at least oneelement that carries out arithmetic and logic operations, and a sequencing and control unit that can change the order of operations based on the information that is stored. Peripheral devices allowinformation to be entered from an external source, and allow the results of operations to be sent out.
Modern computers based on integrated circuits are millions to billions of times more capable than theearly machines, and occupy a fraction of the space. Simple computers are small enough to fit into mobile devices, and mobile computers can be powered by small batteries. Personal computers in theirvarious forms are icons of the Information Age and are what most people think of as "computers".
Computer architecture
Although the technologies used in digital computers have changed a lot since thefirst models appeared in the 40's , most still use the von Neumann architecture , published in the early1940's by John von Neumann , other authors attributed to John Presper Eckert and John WilliamMauchly .
Von Neumann architecture describes a computer with 4 main sections: the arithmetic logic unit,  the control unit , the central memory , and input and output devices ( I / O) . These parts areinterconnected by conductive channels called buses :

The central memory
A computer's memory can be viewed as a list of cells into which numbers can be placed or read. Each cell has a numbered...