Computer+Systems

A computer is an electric device that can perform tasks and calculations to provide logical information based on the instructions that have been given to it.


 * __Types of Computers - __**


 * **Desktop computer** is a personal computer. It is normally used at a single location


 * **Laptop computer** is a personal computer small and light enough to sit on a person lap while in use. Instead of a mouse you use a touching pad. Has a rechargeable battery. Laptop is shape as a notebook. Most laptop are designed in flip form to protect the keyboard and screen.




 * **Handheld computer** is a small portable that is small enough to be held in one hand it also have a small screen and keyboard


 * **Tablet pc** refer to a slate shaped mobile computer device equipped with a touchscreen to operate the computer.


 * **Smartphone** is a mobile phone offering advanced capabilities. There is no industry standard defition of a smart phone. Smartphone is a phone that runs complete operating system software. A smartphone is simply a phone with advanced features like e-mail, Internet and e-book reader capabilities, and/or a built-in full keyboard

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 * **PDA** (personal digital assistant)is a mobile device, also known as palmtop computer. PDAs are used to organize a person's life by taking notes, holding contacts, and connecting to the Internet
 * __ Hardware - __**


 * **Input Devices** - are signals or data received by the system. key board, mouse, scanner, camera may be an input device for a computer.
 * Input devices other than the key board are sometimes called alternate input device Mice, trackballs, and light pens are all alternate input devices.
 * Devices for communication between computers, such as modems and network cards, typically serve for both input and output.
 * Mice and keyboards take as input physical movement that the human user outputs and convert it into signals that a computer can understand.
 * **Output Devices** - are any piece of computer hardware equipment used to communicate the results of data processing carried out by an information processing system to the outside world. Here are some examples of output devices: Monitor, printer, speakers, and projectors.
 * __ Monitor __ - a monitor is the screen on which words, numbers, and graphics can be seen. The monitor is the most common output device. In its most common usage, monitor refers only to devices that contain no electronic equipment other then what is essentially needed to display and adjust the characteristics of an image. Monitors produce a **soft copy** which means something you can see but not touch.
 * __ Printer __ - a printer prints whatever is on the monitor onto paper. Printers are one of the most used peripherals on the computers and are commonly used to print text, images, and /or photos. Printer produces a hard copy which means a document printed on paper. **Hard copies** allow data to be read without the need of a computer.
 * **Impact printers** are the oldest print technologies still in being made. They kind of have qualities that resemble a type writer. It strikes the paper when printing off images or text.
 * **Non-impact printers** are quieter than impact printers because they don’t strike the paper like the impact printers do. Their also a lot quieter and faster than the impact printers. This is because they don’t have as many moving parts.
 * __ Speaker __ - a speaker generates a series of different tones and beeps form your computer. Some speakers are built into the computer and some are separate. Speakers are generally rated in frequency response.
 * __ Projector __ - is displays devices that project a computer image. The computer sends the image data to the video card which then sends the video image to the projector. They are typically for presentations or for viewing videos.
 * **Storage Devices -**


 * **Computer Processors -** The processing unit i s a proportion of a computer system that carries out the instructions of a computer program, and is the primary element carrying out the computer’s functions. The form, design and implementation of CPUs have changed dramatically since the earliest examples, but their fundamental operation remains much the same.


 * __Central Microprocessor__ __:__ It incorporates most or all of the functions of a computer’s central processing unit on a single integrated circuit(IC, or microchip). These microprocessors were used for electronic calculations in the early 1970’s. They are also used for terminals, printers, and various kinds of automation.




 * __Graphics processing unit__ __:__ It’s a specialized processor that offloads 3D graphics rendering from the microprocessor. It is used in embedded systems, mobile phones, personal computers, workstations, and game consoles. Modern GPUs are very efficient at manipulating computer graphics, and their highly parallel structure makes them more effective than general-purpose CPUs.
 * __Physics processing unit:__ is a dedicated microprocessor designed to handle calculations of physics, especially in the physics engine of video games. Examples of calculations involving a PPU might include rigid body dynamics, soft body dynamics, collision detection, fluid dynamics, hair and clothing simulation, finite element analysis, and fracturing of objects.




 * __Digital signal processor__ __:__ is a specialized microprocessor with an optimized architecture for the fast operational needs of digital processing. This requires a large number of mathematical operations to be performed quickly and repetitively on a set of data. Signals are constantly converted from analog to digital, manipulated digitally, and then converted again to analog form.



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 * __Network Processor__ __:__ it’s an integrated circuit which has a feature set specifically at the networking application domain. Network processors are typically software programmable devices and would have generic characteristics similar to general purpose central processing units that are commonly used in many different types of equipment and products.
 * __ Front end processors __ : It’s a small-sized computer which interfaces to the host computer a number of networks, such as SNA, or a number of peripheral devices, such as terminals, disk units, printers, and tape units. Data is transferred between the host computer and the front end processor using a high-speed parallel interface.

Utility programs help you manage, maintain and control computer resources. These programs are made to help you with day to day chores associated with personal computing and to keep your system running at peak performance. Virus scanning software is utility programs designed to protect your computer form computer viruses. Virus scanning software scans your disk each time you insert it into a computer. Your virus scanning software will have to be update on a regular basis. Updates will insure that your virus scanning software will protect you from the most updated viruses. Backup software is a utility program that assists you in backing up your files and even the entire computer hard drive. It will be important for you to back up your files on a regular basis Scandisk is provided with windows computers. Scandisk scan your disk to see if there any potential problems on the disk. Since disks are magnetic media, all disks, including your hard drive can be corrupted. Disk defragmenter software assists you in keeping reorganizing your disk drives. Disk defragmenters gather those free spots and put them together to enable you to save your data in most efficient manner.
 * __ Software - __**
 * **System Software -**
 * **Operating System Software** - controls the basic operations of the computer and manages the computer's files and programs. It acts as a graphical user interface that translates mouse and keyboard actions into appropriate programming code.
 * **Microsoft Windows 98** is a graphical operating system by Microsoft. It was released to manufacturing on May 15, 1998 and to retail on June 25, 1998. Windows 98 is the successor to windows 98 and to retail on June 25, 1998. Windows 98 is the successor to windows95. Like its predecessor, it's a hybrid 16-bit/32-bit monolithic product with an MS-DOS based boot loader.
 * **Windows Millennium Edition**, or Windows ME is a graphical operating system released on September 14, 2000 by Microsoft for windows me ended on July 11, 2006. Windows me was the successor to windows 98 and =, just like windows 98, was targeted specifically a at PC users. It included Internet Explorer 5.5, Windows Media Player 7, and the new Windows Movie maker software, which provided basic video editing and was designed to be easy for home users.
 * **Wii** system software is a set of updatable firmware versions, and software front-end on the wii video console. Updates, which are downloads via the system's internet connection, allow Nintendo to add additional features and software. When a new update becomes available, Nintendo sends a message to connected systems notifying them of the available update. Several game discs, both first-party and third-party games, have included systems software updates so that players who are not connected to the internet can still update their system. Additionally this can 'force' an upgrade by requiring the player to perform the update without which the game cannot be played.
 * **Microsoft DOS** stands for Microsoft Disk Operating System. This is an operating system for x86 based Personal Computers, which was purchased by Microsoft. This was the main operating PC system of the 80's and 90's. The development of this system started in 1981 and it was released in 1982 as MS-DOS. Several versions were released before Microsoft stopped development in 2000. It was the key to Microsoft's growth to a diverse soft ware developing firm.
 * **UNIX** was developed in 1969 by AT&T workers at Bell Labs they were Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas Mcllroy, and Joe Ossanna. Today' s UNIX operates similar to the original. There are several different types or variations of this system. In the late 70's the influence of UNIX in academic circles led to large scale adoption of UNIX by commercial startups. The system was originally named Unics which was a play on the word Multics( Multiplied information and computing). The name refers to the number of simultaneous users on the computer the operating system could support. The system eventually could support two and so it was changed to UNIX.
 * Both MS-DOS and Unix are a **command line interface** operating system meaning that you must type in programming code to operate a computer.
 * **Application Software** - is computer software designed to help the user to perform a particular task. Such programs are also called software applications, applications or apps. Typical examples are word processors, spreadsheets, media players, and database applications.
 * **Word processing**- A word processor is a computer application used for the production (including composition, editing, formatting, and possibly printing) of any sort of printable material.
 * **Spreadsheet**-A spreadsheet is a computer application that simulates a paper, accounting worksheet.spreadsheets are frequently used for financial information because of their ability to re-calculate the entire sheet automatically after a change to a single cell is made.
 * **Database**-A database is an integrated collection of logically-related records or files consolidated into a common pool that provides data for one or more multiple uses
 * **Presentation**- is the practice of showing and explaining the content of a topic to an audience or learner. Presentation program, such as microsoft powerpoint, is often used to generate the presentation content.
 * **Graphics**-are visual presentations on some surface, such as a wall, canvas, computer screen, paper, or stone to brand, inform, illustrate, or entertain. Examples are photographs, drawings, Line Art,
 * **Communication**- is a process of transferring information from one entity to another.
 * **Voice/speech recognition**- converts spoken words into text.


 * __ Memory - __**


 * **RAM -** Random Access memory is also know has RAM. RAM is the moist common type of memory used in a computer.RAM is mostly know for “random access” because you can access memory, but only if you know the row and column that intersect at that cell. The two types of RAM are DRAM( Dynamic Random Access Memory) and SRAM(Static Random Access Memory). DRAM is type of access memory that needs to refresh. SRAM is type of memory that has very high speed. The RAM is the best type of memory you can have.




 * **ROM -** Read Only Memory is a storage which is written and then cannot be changed. Once written the only way to destroy the data is to destroy the device holding the data. ROM mean read only memory would be a CD or a DVD disc. But once you have written on it cannot be change, with the exception of Re Writables which were designed specifically for a good purpose even though it cannot be re written on the fly.