Computer Programming Basic 1

Multiple Choice

Computers use ______________ number system.

• Binary

• Decimal

• Hexadecimal

• Octa decimal

Fill in the Blank

The value of octa decimal value 017 is ____.

Basic Computer Principles

​Computers

Computers come in many forms, from the traditional desktop PC to portable devices such as laptops, tablets and even smartphones. However, a number of basic elements are generally found within most computing devices used by ordinary people. There are many additional types of computer used only within certain specialized contexts such as supercomputers and servers. The basic principles of how a computer operates are generally the same whatever its purpose is.

Basic Computer Principles

​Operating System

The operating system on a computer is what bridges the gap between the hardware and the user. Common operating systems include Windows, Mac OS and Linux, all of which are available in varying forms. The operating system in a computer communicates with and controls hardware elements including the hard disk, memory, processor, input and output devices. At the opposite end, the operating system presents an interface allowing users to control the computer.

Basic Computer Principles

Applications

Most computers have a number of applications installed on their operating systems. These can facilitate a very wide range of functions, including those for work, personal life and entertainment. For office and organizational use, programs such as Microsoft Office and Open Office include applications for word processing, spreadsheets and calendars. Graphic design and image editing software is also common, as are email clients and Web browsers for Internet access.

Basic Computer Principles

Input

Input devices on a computer vary depending on the type of computing device in question. For desktop and laptop PCs, input is typically provided through a keyboard and mouse. Most keyboards used in the West adopt a QWERTY layout for text input, as well as number pads and other function keys. A mouse may be provided as part of a laptop, in the form of a touch-pad just below the keyboard area. Alternatively a mouse may be a separate component which plugs into the computer and controls applications through movement and button clicks. Some smartphones and tablet PCs use touchscreen interfaces, in which the screen is used for both display and user interaction.

Basic Computer Principles

Output

Output devices in computers typically include visual and auditory elements. The main output component in a computer tends to be the monitor, which presents a graphical display to users. The monitor may be a separate element connected to the computer through cables, or may be part of the same hardware item as in a laptop or tablet PC. Audio output may be provided through built-in speakers which form part of the computer or monitor element. Alternatively, audio output can be captured through headphones plugged into an audio output port.

Basic Computer Principles

Networking

Computers are regularly networked together, allowing users to share data and applications. Within workplaces and organizations, it is common for computers to be linked via a network, providing access to shared programs and databases. The Internet is also a way in which computers are networked, connecting vast numbers of people around the world from domestic, public and work environments. Internet connections allow computers to access websites and use communication techniques such as emailing, instant messaging and social networking.

Basic Computer Principles

Input & Output Devices

The concept of input and output devices is much simpler than it sounds. These devices—most commonly associated with computers—are the basic peripheral hardware you use on a daily basis. Input hardware serves to send data into the computer's CPU, while output devices send data outwards to the user.

Basic Computer Principles

Mouse & Keyboard

The two most common forms of input related to computers are the mouse and keyboard. They serve as the gateway of control for the computer. They allow the user to manipulate and dictate tasks—ranging from surfing the Internet to writing documents. Keyboards most commonly come in the form of "QWERTY" keyboards, which have an arrangement that originates from typewriters over a century ago. Mice now come in many types, from traditional cord mice, to wireless and laptop mice.

Basic Computer Principles

Monitor

As humans are visually-focused, the most common output device is the monitor. The monitor visually relays an image, which is created by the computer's operating system. The computer user sends manipulations through input devices, which enter the motherboard and processor, ultimately manifesting themselves in the operating system. Older monitors—much like TVs—have CTRs, or cathode ray tubes. Newer models usually feature LCD screens, which have a greater resolution and are lighter in weight.

Basic Computer Principles

Printer & Scanner

Two very similar pieces of hardware perform a closely related function; however, each does the exact opposite of the other one. Printers—an output device—produce images or text from the computer. Scanners, on the other hand, input text and image photos into the computer. A digital representation can then be modified and sent electronically if desired.

Basic Computer Principles

Microphone & Speaker

High-quality audio in computers has become more commonplace since the turn of the century. Almost all computers come with built-in speakers; however, you can hook up external speakers as a more enhanced output device—usually through the use of a USB port. Speakers are usually present as an input device; however, they usually have low quality. They allow voice transmission—through the Internet—as well as voice recording.

Basic Elements of Computer

Computers are general-purpose machines that are designed to follow instructions to complete data processing tasks. Although the specific architecture of different types of computers may be different, all computers accomplish data processing using five basic elements of the computer system: input, output, datapath, control and memory. Each of these elements is associated with one or more hardware devices that are built into the computer or connected externally.

Input & Output

Communication with the outside world takes place through the input and output elements of the computer system. Data is input into a computer through external hardware devices like mice, keyboards, touchscreens and storage devices. Once data has been processed, it can be converted to a human-readable format for output to devices like printers, displays, speakers or headphones. The computer can also convert data to other output formats, such as electrical signals for controlling automated equipment.

Datapath Element

The datapath element is made up of several units that perform data processing within the CPU (central processing unit), which is often referred to as the brains of the computer. The CPU interprets programming instructions and controls internal and external devices. One of the most important units within the CPU is the ALU (arithmetic logic unit), which performs arithmetic and logical operations on data. Some computers have a dedicated graphics processing unit (GPU) to support high-speed display of complex visual images. The datapath also contains circuits and registers that track system states, such as the program counter for the currently executing software.

Control Element

The control element of the computer is responsible for movement of data between memory and the CPU. This element coordinates the execution of program instructions with all the other elements of the computer system by providing timing and control signals. The job of the control element is done by the control unit (CU), which on most modern computers is part of the CPU. The control unit is often described as the central nervous system of the computer.

Memory Element

Computers use both internal and external memory when performing operations. Internal memory is used to hold the software instructions and related data for programs that are currently executing. Internal memory consists of RAM (random access memory), which is temporary because it retains data only while power is applied. When the computer is turned off, the memory clears. Data which is not being used by the computer is usually stored in external memory on devices like hard drives and flash drives.