Introduction to Computers and the internet The Amazing Computer Introduction to Computers and the internet

The Computer A computer is an electronic device that processes data and converts it into useful information. Computers come in many varieties from Personal Computers (PC’s), Macintosh (Mac), Hand-held Device (Cellphones).

History of Computers Development of computers began with many early inventions: The abacus helped early societies perform computations (c. 3000 B.C.) The Pascaline used moveable dials to add numbers with up to eight digits (1642).

Nineteenth-Century Inventions The nineteenth century brought further inventions: Charles Babbage’s Difference Engine and later his Analytical Engine defined many basic components of today’s computers. The arithometer (1820) performed four basic mathematical functions: + - * /. Herman Hollerith developed a system to aid in tabulating data from the 1890 U.S. Census using punch cards. Arithometer

First-Generation Computers During World War II, the first generation of modern computers was introduced: Colossus (the Turing machine) was developed in England to decode encrypted German messages. ENIAC was developed in the U.S. to calculate ballistic missile trajectories. EDVAC was designed by John Von Neumann and it featured a central processing unit. UNIVAC was the first commercially available computing device.

Second-Generation Computers The second generation of computers (c. 1956) was marked by: A shift from bulky vacuum tubes to transistors. A shift in programming from physically rerouting cables to “software” stored on punch cards and tape storage. The emergence of machine and assembly languages.

Third-Generation Computers With the invention of integrated circuits (ICs), computers became smaller and more powerful; this is know as the third generation computers. ICs are: Smaller than transistors Produce less heat Allow multiple components to fit on a smaller chip

Fourth-Generation Computers Fourth Generation Computers are computers became smaller and more affordable, and available to small businesses and individuals. MITS Altair 8800 (1974) Apple I, II Commodore PET IBM PC (1981) Macintosh (1984) The computers we use today are also considered fourth generation computers

Computer System Computer system consists of four parts: hardware, software, one or more users, and data. Hardware – the physical devices that make up the computer are called the hardware. It is any part of the computer that you can touch – monitor, keyboard, mouse, joystick, desktop and etc… Even the components inside the computer – motherboard, circuit board, memory and so on are hardware pieces.

Computer System Software – is a set of instructions that makes the computer perform tasks. In other words, the software tells the computer what to do. A program is any piece of software. Types of programs are – Microsoft Office (Word, PowerPoint, Excel), Adobe Products, Internet Browsers, Windows OS, and so forth. Users – are people who become the computer operators. A computer is possible to operate without a human siting at the computer, but people (users) are still needed to design, build, program and repair a computer system.

Computer System Alphabet Binary representation A 01000001 B 01000010 C 01000011 D 01000100 E 01000101 F 01000110 G 01000111 Data – consist of individual facts or bits of information, which by themselves may not make much sense to a person. The computer reads and stores data of all kinds – whether they are words, numbers, images or sounds – in the form of numbers. As such all data is digital, this digital data is read by the computer and presented to you in information you can understand.

Inside the Machine

Inside the Machine The motherboard is a rigid rectangle piece inside the computer that connects all the exterior hardware to the interior hardware. All the data is collected from the use of the keyboard, mouse, CD Rom, USB and etc… (input devices) where it is transmitted through the motherboard and is processed through the processor, and the information is then sent to the monitor, speakers, printer, projector and etc.. (output devices).

Inside the Machine Processor – the procedure that processes data into useful information is called processing. The processor is like the brain of the computer; it organizes and carries out instructions that come from either the user or the software. Inside a PC there are microprocessors like Intel Pentium, AMD, and IBM. The processor is also called the CPU (Central Processing Unit). The computer system is usually referred to via the CPU type.

Inside the Computer The Random Access Memory (RAM) in your computer is like an electronic scratch pad. When you launch a program, it is loaded and runs rom the RAM. As new data is entered into the computer it is also stored into the RAM. Data can both be written to and read from RAM. However, once the computer is shut off the data will disappear from the RAM. The more RAM (in bytes) a computer has, the faster the programs will run. Thus a 2 GB of RAM is much slower than a 4 GB of RAM. Think of it as a big filing cabinet that keeps things ready for the CPU  Note, RAM is also called memory and is interchangeable with RAM.

Input and Output Devices An input device accepts data and instructions from the user or from another computer. Common input devices are keyboards and a mouse. Other input devices can be a microphone, a joystick, a scanner, and a touchpad. An output device returns the processed data to the user, or another computer, in a form either is able to read and understand. Common output devices are monitors and printers. Other output devices are speakers, projection machines and a touch screen.

Back Storage A computer can function with only a processor, memory (RAM), input and output devices. But for a computer to be useful it needs a hard drive. A hard drive is an electronic filing cabinet that permanently stores and holds data. This is where the files you save to your computer are stored, the software that is on your computer and any other data that is added to your computer like cache from the internet. Front

Storage People think Memory and Hard Drive’s are the same thing and use them incorrectly. Here are three main differences between the two: There is more room in hard drives than there is in RAM Contents are retained in a hard drive when the computer is turned off, whereas the programs or the data on the RAM disappears when you shut the computer off. Hard drive’s are very slow and takes a longer time to load information than RAM, but this makes a hard drive much cheaper than RAM.

Storage While a hard drive is a main form of storage, there are other types of storages that we use everyday: CD’s (I know, old school but still great way to store data and share it). CD’s can be just writeable and re-writeable. Portable Hard Drives. Useful to back up your computer in case your main computer crashes. USB this is the 21st century type of CD’s. It can store massive amount of data on a small piece of hardware.