Week 3 - Session 2. Programming Language: Machine, Assembly, High-Level Language

Purpose; Today our main objectives are to find out more further information about what is program, programming language, programming and who is programmer.

Programming language is a set of words, numbers, symbols which permits programmer who uses computer to communicate instructions to a computer and it serves as a tool to write or create programs. Moreover, It is a unique language to connect programmer and computer

Types or PL

There are main two types of computer languages
1. Low-level language
2. High-level Language

In turn, Low-level language shows following characteristics namely, they are machine dependent language, tedious and time-consuming and each instruction represents a single machine instruction
The next one High-level language is machine in dependent language, more user friendly and every instruction can indicate different and several machine instructions.

1.Low- level language has two types Machine (the first generation) Language and Assembly language (the second generation)


2.High-level languages -s more powerful than assembly language, allows user to work more English-like Environment and it includes 3 kinds as following, namely the third, fourth and fifth generation languages




Generations of programming languages

The first and second generations: We start out with the first and second generation languages during the period of 1950-60, which to many experienced programmers will say are machine and assembly languages. Programming language history really began with the work of Charles Babbage in the early nineteenth century who developed automated calculation for mathematical functions. Further developments in early 1950 brought us machine language without interpreters and compilers to translate languages. Micro-code is an example of the first generation language residing in the CPU written for doing multiplication or division. The second generation of programming language like AUTOCODER, SAP and SPS

The third-generation: Throughout the early 1960's till 1980 saw the emergence of the third generation programming languages. Languages like ALGOL 58, 60 and 68, COBOL, FORTRAN IV, ADA and C are examples of this and were considered as high level languages. Most of this languages had compilers and the advantage of this was speed. Independence was another factor as these languages were machine independent and could run on different machines. The advantages of high level languages include the support for ideas of abstraction so that programmers can concentrate on finding the solution to the problem rapidly, rather than on low-level details of data representation

 

The Fourth generation: Features evident in fourth generation languages quite clearly are that it must be user friendly, portable and independent of operating systems, usable by non-programmers,  which was not possible using COBOL or PL/I. Standardisation however, in early stages of evolution can inhibit creativity in developing powerful languages for the future. Examples of this generation of languages are IBM's ADRS2, APL, CSP and AS, Power Builder, Access.

The fifth generation: The 1990's saw the developments of fifth generation languages like PROLOG. This means computers can in the future have the ability to think for themselves and draw their own inferences using programmed information in large databases. Complex processes like understanding speech would appear to be trivial using these fast inferences and would make the software seem highly intelligent

Week 3 - Session 1. Software layers: Operating System, drivers, system software, application programs,

I hope this session will help me greatly in order to get more information about operating System, drivers, system software, application programs.

What is software?

Software is the general term for information that's recorded onto some kind of medium. For example, when you go to the video store and rent or buy a tape or DVD, what you're really getting is the software that's stored on that tape or disk. Your VCR or DVD player are hardware devices that are capable of reading the software from a tape or disk and projecting it onto your TV screen, in the form of a movie.

Your computer is a hardware device that reads software too. Most of the software on your computer comes in the form of programs. A program consists of "instructions" that tell the computer what to do, how to behave. Just as there are thousands of albums you can buy on CD for your stereo, and thousands of movies you can buy to play on your VCR or DVD player, there are thousands of programs that you can buy to run on your computer.

Categoriws of software:

• System Software
• Aplication software
• programming language 

The System software controls and maintains the operations of the computer and its devices.

The Application software makes users more productive and assist them with their task

The Programming language enables people to communicate instructions to a computer.


Software layers

A systems software can be partitioned using the concept of software layers.

Software layers are where each ‘layer’ of a system deals with a certain function of a system which, usually, gets more and more detailed as you burrow down into the layer stack.

Application program

An application program sometimes shortened to application is any program designed to perform a specific function directly for the user or, in some cases, for another application program. Examples of application programs include word processors; database programs; Web browsers; development tools; drawing, paint, and image editing programs; and communication programs. Application programs use the services of the computer's operating system and other supporting programs. The formal requests for services and means of communicating with other programs that a programmer uses in writing an application program is called the application program interface (API).


Operating system

An operating system, or OS, is a software program that enables the computer hardware to communicate and operate with the computer software. Without a computer operating system, a computer would be useless.

OS receives order from the user via application program

It has programs and routines that control all accesses to hardware

Higher levels are protected from any issues

when the OS determines its safe to proceed, direct calls to device drivers are performed

Device drivers

device driver is a program that controls a particular type of device that is attached to your computer. There are device drivers for printers, displays, CD-ROM readers, diskette drives, and so on. When you buy an operating system, many device drivers are built into the product. However, if you later buy a new type of device that the operating system didn't anticipate, you'll have to install the new device driver. A device driver essentially converts the more general input/output instructions of the operating system to messages that the device type can understand.


Protecting your computer

Computer viruses are deadly. They often spread without any apparent contact and can be a nuisance, or even worse, fatal to your computer. Individuals who create these viruses estimated at 10-15 new ones a day--are the electronic version of terrorists. Their goal is to inflict havoc and destruction on as many people as possible by disabling, stealing, damaging, or destroying computer and information resources. Often, they have no specific target in mind, so no one is safe. If you access the Internet, share files or your computer with others, or load anything from diskettes, CDs, or DVDs onto your computer, you are vulnerable to viruses. Fortunately, there are good guys working just as hard as the hackers to develop cures for viruses as quickly as they send them off into cyberspace. And there are many things you can do to keep your computer from catching viruses in the first place.

Week 2 - Session 3. Computer hadware basics

Computer Hardware Basics:

Storage devices, I/O devices and other peripheral devices

Today is a wonderful day, because I have ICT class. I believe that I will get more information than I expected and more than usual. therefore, I hope, I will satisfy my hunger with real knowledge today. So, main objective is to find answers to the following inquiries.

What is input?

An input device is a peripheral used to transfer data from the outside world into a computer system. In other words, it is any machine that feeds data into a computer. 
Examples of input devices are:
Keyboard                   
Mouse
Light pen
Joystick
Scanner
Touch screen
Microphone
Graphic tablet
Magnetic-s


The keyboard:
The set of typewriter-like keys that enables you to enter data into a computer. Computer keyboards are similar to electric-typewriter keyboards but contain additional keys. The keys on computer keyboards are often classified as follows:

alphanumeric keys -- letters and numbers  

special keys -- function keys, control keys, arrow keys caps lock key, and so on. 

Pointing Devices:
A pointing device is an input interface that allows a user to input spatial (i.e., continuous and multi-dimensional) data to a computer. CAD systems and graphical user interfaces(GUI) allow the user to control and provide data to the computer using physical gestures — point, click, and drag — for example, by moving a hand-held mouse across the surface of the physical desktop and activating switches on the mouse. Movements of the pointing device are echoed on the screen by movements of the pointer and other visual changes.



Game controllers:  
A game controller is a device used with games or entertainment systems used to control a playable character or object, or otherwise provide input in a computer game. A controller is typically connected to a game console or computer by means of a wire, cord or nowadays, by means of wireless connection. Controllers which have been classified as game controllers are keyboards, mice, game pads, joysticks, etc. Special purpose devices, such as steering wheels for driving games and light guns for shooting games, are also game controllers. Devices such as mice and keyboards can be emulated with a game pad through the use of programs such as 'JoyToKey'.
The main function of a game controller is to govern the movement/actions of a playable body/object or otherwise influence the events in a video or computer game. The type of controller used in a game depends on the genre of the game being played (i.e. Steering Wheel controllers for driving games, yoke like for flying, etc.).


Digital cameras:
A digital camera (or digicam) is a camerathat takes video or still photographs, or both,digitally by recording images via an electronic image sensor. It is the main device used in the field of digital. Most 21st century cameras are digital.

Front and back of Canon PowerShot A95

Digital cameras can do things film cameras cannot: displaying images on a screen immediately after they are recorded, storing thousands of images on a single small memory device, and deleting images to free storage space. The majority, including most compact cameras, can record moving video with sound as well as still photographs. Some can crop and stitch pictures and perform other elementary image editting. Some have a GPS receiver built in, and can produce Geotagged photogaraphs.

Voice recognition device:

Ability of a computer, computer software program, or hardware device to decode the human voice into digitized speech that can be interpreted by the computer or hardware device. Voice recognition is commonly used to operate a device, perform commands, or write without having to operate a keyboard, mouse, or press any buttons. For example, a user could say "open Internet" and the computer would open an Internet browser and allow that user to browse the Internet.

Scanners and reading devices: Scanner and reading devices and the associated software can be of assistance to students who are blind, have visual impairments or specific learning difficulties including dyslexia.
The stand-alone scanner reader takes text and converts it to speech output. Optical character recognition(OCR) software can read pages containing tables or columns and work its way fairly successfully through material at different orientations. OCR may also be used on a computer with a separate scanner.
Some specialist computer programs offer text highlighting, book marking and note-taking features as well as various colours and contrast modes for viewing.
There are also pen scanners - small amounts of text, such as quotes, can be taken from books or journals and downloaded to a computer.

What is output

Output devices are things we use to get information OUT of a computer.
Here are some examples of output devices.

Monitor - A monitor is the screen on which words, numbers, and graphics can be seem.  The monitor is the most common output device.
Compact Disk - Some compact disks can be used to put information on.  This is called burning information to a CD. NOTE:  A CD can also be an input device.
Printer - A printer prints whatever is on the monitor onto paper.  Printers can print words, numbers, or pictures.
Speaker - A speaker gives you sound output from your computer.  Some speakers are built into the computer and some are separate.
Disk Drives - A disk drive is used to record information from the computer onto a floppy disk or CD.
Floppy Disk - A floppy disk is used to record information on.  The information is stored on the floppy disk and can be used later or used on another computer.
Headphones - Headphones give sound output from the computer.  They are similar to speakers, except they are worn on the ears so only one person can hear the output at a time.

What is storage
A computer storage device is any type of hardware that stores data. The most common type of storage device, which nearly all computers have, is a hard drive. The computer's primary hard drive stores the operating system, applications, and files and folders for users of the computer.