University Mohamed Khider- Biskra
Faculty of letters and Languages
Department of Foreign Languages-Division of English
English for Specific Purposes
Level: Third year
Instructor: Mrs. SAID SALHI -A
English for Computer Science
Computer science is a discipline that spans theory and practice. It requires thinking both in abstract terms and in concrete terms.
The practical side of computing can be seen everywhere. Nowadays, practically everyone is a computer user, and many people are
even computer programmers. Getting computers to do what you want them to do requires intensive hands-on experience. But
computer science can be seen on a higher level, as a science of problem solving. Computer scientists must be adept at modeling and
analyzing problems. They must also be able to design solutions and verify that they are correct. Problem solving requires precision,
creativity, and careful reasoning.
Computer science also has strong connections to other disciplines. Many problems in science, engineering, health care, business,
and other areas can be solved effectively with computers, but finding a solution requires both computer science expertise and
knowledge of the particular application domain. Thus, computer scientists often become proficient in other subjects.
Finally, computer science has a wide range of specialties. These include computer architecture, software systems, graphics, artifical
intelligence, computational science, and software engineering. Drawing from a common core of computer science knowledge, each
specialty area focuses on particular challenges.
Computer Science is practiced by mathematicians, scientists and engineers. Mathematics, the origins of Computer Science,
provides reason and logic. Science provides the methodology for learning and refinement. Engineering provides the techniques for
building hardware and software.
Computer Science: The Profession
Computer science is a discipline that involves the understanding and design of computers and computational processes. In its most
general form it is concerned with the understanding of information transfer and transformation. Particular interest is placed on
making processes efficient and endowing them with some form of intelligence. The discipline ranges from theoretical studies of
algorithms to practical problems of implementation in terms of computational hardware and software.
Because of the rapid evolution it is difficult to provide a complete list of computer science areas. Yet it is clear that some of the
crucial areas are theory, algorithms and data structures, programming methodology and languages, and computer elements and
architecture. Other areas include software engineering, artificial intelligence, computer networking and communication, database
systems, parallel computation, distributed computation, computer-human interaction, computer graphics, operating systems, and
numerical and symbolic computation.
A professional computer scientist must have a firm foundation in the crucial areas of the field and will most likely have an in-depth
knowledge in one or more of the other areas of the discipline, depending upon the person's particular area of practice. Thus, a well
educated computer scientist should be able to apply the fundamental concepts and techniques of computation, algorithms, and
computer design to a specific design problem. The work includes detailing of specifications, analysis of the problem, and provides
a design that functions as desired, has satisfactory performance, is reliable and maintainable, and meets desired cost criteria.
Clearly, the computer scientist must not only have sufficient training in the computer science areas to be able to accomplish such
tasks, but must also have a firm understanding in areas of mathematics and science, as well as a broad education in liberal studies
to provide a basis for understanding the societal implications of the work being performed.
Computer Science Areas
The nine subject areas defining the core of computer science are:
1.
2.
Algorithms and Data Structures: This area deals with specific classes of problems and their efficient solutions. The
performance characteristics of algorithms and the organization of data relative to different access requirements are major
components.
Architecture: Methods of organizing efficient, reliable computing systems provide a central focus of this area. It includes
implementation of processors, memory, communications, and software interfaces, as well as the design and control of
large computational systems that are reliable.
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3.
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9.
Artificial Intelligence and Robotics: The basic models of behavior and the building of (virtual or actual) machines to
simulate animal and human behavior are included here. Inference, deduction, pattern recognition, and knowledge
representation are major components.
Database and Information Retrieval: The area is concerned with the organization of information and algorithms for the
efficent access and update of stored information. The modeling of data relationships, security and protection of
information in a shared environment, and the characteristics of external storage devices are included in this area.
Human-Computer Communication: The efficient transfer of information between humans and machines is the central
focus of this area. Graphics, human factors that affect efficient interaction, and the organization and display of information
for effective utilization by humans are included.
Numerical and Symbolic Computation: General methods for efficiently and accurately using computers to solve equations
from mathematical models are central to this area. The effectiveness and efficiency of various approaches to the solution
of equations, and the development of high-quality mathematical software packages are important components.
Operating Systems: This area deals with control mechanisms that allow multiple resources to be efficiently coordinated
during the execution of programs. Included are appropriate services of user requests, effective strategies for resource
control, and effective organization to support distributed computation.
Programming Languages : The fundamental questions addressed by this area involve notations for defining virtual
machines that execute algorithms, the efficient translation from high-level languages to machine codes, and the various
extension mechanisms that can be provided in programming languages.
Software Methodology and Engineering: The major focus of this area is the specification, design, and production of large
software systems. Principles of programming and software development, verification and validation of software, and the
specification and production of software systems that are safe, secure, reliable, and dependable are of special interest.
A. Computer Basics
What is a Computer?
Basically, a computer is an electronic machine that can carry out calculations and is able to store information. In order to do these
things, a computer uses different programs for specific tasks. For example, it has a word processing program for typing letters and
a program called a Web Browser for searching and browsing the internet. Computers also come in different shapes and sizes e.g.
laptops, desktops and tablets but they are all able to perform the same or similar tasks.
Beginnings
The first programmable computer, designed by Charles Babbage in the 1830s, was mechanical rather than electronic. Unfortunately it
was never built, and it wasn't until World War II that British code breakers built Colossus, the world's first programmable and fully
electronic computer. However, Colossus still didn't include a number of elements present in modern computers. Finally, after the
war, a complete computer was built in Manchester by the great mathematician Alan Turing, who had worked with the code
breakers.
From Science Project to Everyday Tool
Computers were initially of interest only to scientists and engineers. But from the human–computer interaction theories of mouse
inventor Douglas Engelbart in the 1960s to the release of the Apple Macintosh computer in 1984, they became easier to use and more
capable of tasks that ordinary people could carry out.
Now, with the spread of personal computers (PCs), mobile phones, notebooks and tablets, computers have become part of our
everyday lives. It's almost impossible to imagine modern society without them.
Highlights in the development of the computer
 Computers started out as huge racks of glass valves and wires that occupied multiple rooms and weighed tons. Now they
can fit on tiny microchips that are barely larger than an ant and are millions of times more powerful than the first ones.
 Computers have a huge variety of uses. Originally employed to break enemy codes and calculate artillery trajectories,
they're now used for everything from word processing and spreadsheets to mobile phones and playing games.
 The number of computers in the world has risen incredibly. Urban myth has it that, in the 1950s, the head of IBM
estimated a global market for five – yes, five – computers. But within the next few years, it's expected that there will be 2
billion computers – and that figure doesn't even include computers built into other devices.
 In the late 1960s, the American government created ARPANET, a network that allowed the few university and military
computers in the US to talk to each other. This eventually turned into the internet, a global web that connects well over a
billion computers – and people – to each other.
What is a PC?
The letters 'PC' stand for 'personal computer' – that is, a computer that can fit on a single desk for use by ordinary people, as
opposed to a huge mainframe or supercomputer.
Although the acronym technically refers to any such computer, it has come to mean the multi-purpose machines that usually run
the Microsoft Windows operating system, as opposed to the Macintosh machines made by Apple.
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Key Benefits and Features of the PC
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PCs used to be known as 'IBM-compatibles' as they were based on systems built by the IBM Corporation. However, the
machines went on to be made by so many other companies that the term fell out of use – in fact, IBM has completely
stopped making PCs.
PCs are mainly identified by their use of the Windows operating system. An operating system is the background software
that runs everything else on top of it. Windows is the best-selling 'OS' in the world.
Windows is not the only OS that PCs can use. Linux is a free 'open source' system that has been created by volunteers
around the globe. It's very popular among the technically minded, but is unlikely to suit a beginner.
PCs are capable of many functions, including word processing, playing music, videos and games, accessing the internet,
and much more.
PCs have a number of advantages over Apple Macs: They're generally cheaper, they have far more software available
(especially games) and, as they're more popular, they tend to have fewer compatibility problems on the internet. They're
also much more open to tinkering, if you're so inclined.
The PC's Achilles heel is its vulnerability to all sorts of viruses and malware. So far Apple Macintoshes have proved to be
much more resilient against viruses and other threats. With a PC, you can't afford not to invest in antivirus programs and
keep them up to date.
What is a Mac?
The nickname 'Mac' refers to the series of Macintosh computers made by Apple Inc. since 1984. With its very first model, Apple is
largely credited with starting the trend of making computers that are easy for ordinary people to use and promoting the idea that
anyone can find a computer useful. Macs are particularly popular with graphic and web designers.
Macs' main rivals are PCs running the Microsoft Windows operating system (i.e. the background software that runs everything
else).
What is a Tablet Computer?
Tablets are small, flat computers with touchscreens that are between a book and a magazine in size. They're like large versions of a
smartphone. The most popular tablet computers at the time of writing are the Apple iPad and the Samsung Galaxy Tab.
Key Features and Benefits of Tablet Computers
 Tablet computers are usually less powerful than 'proper' PCs. Instead of working via a fully fledged operating system
(OS) such as Windows, a tablet will generally use an extended version of a smartphone OS.
 Small enough to fit in the hand but large enough to display a lot of text at a decent size, tablets are intended to bring the
feeling of a book or magazine to a computer.
 The tablet is ideal for browsing the web, its size and shape making it easy to read and hold. All tablets include wifi to help
you browse, with many including a 3G or 4G connection as well, allowing you to connect to the internet from anywhere.
 Just like smartphones, tablet computers will usually have access to an 'app store' where you can purchase and download a
huge number of applications (or 'apps'). These can perform any number of things, from word processing to games – and
are also designed for the tablet's larger screen.
 Tablet computers are also excellent media players. They'll play music on headphones or through their own speakers. Even
more enticingly, videos look excellent on the relatively large screen.
 Most tablets include e-reader software that allows you to download books and other written material from the internet
and read it on the machine. However, even though the ‘e-ink’ screens of dedicated e-reader devices such as the Amazon
Kindle are much easier on the eyes for intensive reading, they’re not considered tablets as they’re not multifunctional
enough. With the new launch of Kindle Fire, the reader element is an application and the screen is in colour like other
tablets and it offers more functionality.
 Generally tablet computers have smaller screens than standard computers, which some people may find difficult to use.
 Some people may also find the access method of finger or pen more difficult, particularly if using a virtual onscreen
keyboard, where the letters are smaller and therefore it is a smaller target.
What is a Smartphone?
Smartphones are the new breed of mobile phones that have multiple functions similar to those you might expect from a regular
computer. Apple's iPhone is the most popular example, with over 100 million handsets sold by 2011, but competitors like
BlackBerry are catching up fast. Almost every mobile phone you can buy now will have some sort of smartphone capability.
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Smartphones' key Benefits and Features
 Smartphones are about the same size, shape and weight as a normal mobile phone.
 They've usually got a large amount of memory so that that they can store and carry music, photographs, videos and
information.
 Smartphones can access email and the web wherever you are, either through a portable 3G connection or through a wifi
connection if one's available.
 Smartphones have the ability to run applications known as 'apps' – computer programs that run on your phone. Apps can
provide a wide range of functions, from word processors to games and foreign language translators. It's almost like
having a fully functional computer in your pocket.
 Of course, smartphones can also make and receive phone calls and text messages!
 Smartphone costs vary a great deal, according to model and network provider. You can expect to pay between £150 and
£300 on an annual contract or around £500 on a pay-as-you-go basis.
What is Android?
Android is an operating system (OS) for smartphones developed by Google, similar to the way in which Windows is an OS for
PCs. It's the software that constantly runs on the phone, managing its more basic functions and supporting any apps (applications)
that are run on top of it.
What is an iPod?
The iPod is a pocket-sized portable music-playing device produced by Apple and sold across the world. It's the best-known family
of MP3 players and comes in a variety of models.
Features and Benefits of an iPod
 iPods can store several thousand songs, the exact number depending on the model.
 The iPod Touch and iPod Classic can play video.
 The iPod Touch can hold up to 25,000 photos as well and multiple 'apps' and games.
 The iPod Nano has a radio.
 It's easy to connect to a computer and manage an iPod's music library and playlists via iTunes.
 The new iPod Touch has 'FaceTime' enabled, a video-calling facility between iPod Touches and various other Apple
products such as the new iPad 2 and the iPhone 4.
 iPod Classic models store media on an internal hard drive, while all other models use flash memory, which means the
devices can be smaller and thinner.
B. Using the Net
What is the Internet?
The internet is a telecommunications network that uses telephone lines, cables, satellites and wireless connections to connect
computers and other devices to the World Wide Web. All modern computers can connect to the internet, as can many mobile
phones and some televisions, video game consoles and other devices.
The Internet can be used to:
 access a huge 'library' of information from the millions of websites around the world that make up the World Wide Web
 send and receive email messages
 share photographs and video clips with your friends and family
 buy goods and services (and often save money!)
 carry out online banking
 use Skype to make free phone calls to other computer users
 play games with other people online
 catch up on TV and radio programmes that you've missed – or watch them again
 learn something new with an online course.
What is 3G ?
 While using your mobile phone or smartphone, you may have noticed ‘3G’ in the top of your screen, or been informed
that you cannot perform a particular function over 3G.
 3G or 3rd generation mobile telecommunications is a generation of standards for mobile phones and mobile
telecommunication services.
 Largely made popular by devices such as Apple’s iPhone, 3G revolutionised the way mobile phones connect to the
internet by allowing a constant connection that no longer requires dialing up to perform tasks like checking your email or
surfing the web.
 Laptop users can also buy ‘dongles’ ,which plug into their computers to allow them to access the internet via 3G.
 As a result, the burden on 3G mobile networks has been growing, meaning that some applications and web services only
allow you to use them over a wireless internet connection to reduce the load on the network.
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What is Bandwidth?
'Bandwidth' describes the rate at which data can be transferred to your computer from a website or internet service within a
specific time. Therefore the amount of bandwidth you have (the bandwidth 'strength') determines the efficiency and speed of your
internet activity – that is, when you open web pages, download files and so on.
A useful analogy is a pipe with water running through it – the wider the pipe, the greater the volume of water that can flow
through it. The same applies to bandwidth strength and the flow of the volume of data.
Bandwidth is generally measured in ‘bits per second' or sometimes ‘bytes per second'.
What is a Router?
A router is a device that directs data traffic along specific routes. A router sends information, such as email and the content of web
pages, between your computer and the network server. It also connects networks and acts as a filter at a ‘gateway’ between them,
channelling information to the correct IP address, unique to each computer. A router is also the device that keeps single computers,
or entire networks, connected to the internet.
What is Wifi?
Wifi, pronounced ‘why-fy’, is wireless internet that, quite literally, enables access to broadband internet without the use of wires.
Instead, it uses radio waves in the same way that your mobile phone or television does. This means that you can use your laptop or
other internet-enabled device anywhere in a building without having to install extra cables or phone lines, as long as the radio
waves can reach the device that links the computer to the radio waves.
Wifi also allows several computers, laptops and the like to be connected to the internet at any one time, essentially creating a
network between all the devices in your home or office. Wifi is also increasingly found in public places, such as libraries and cafés,
making it easy to access the internet while on the move.
C. Email and Skype
What is Email?
Email is short for 'electronic mail'. Similar to a letter, it is sent via the internet to a recipient. An email address is required to receive
email, and that address is unique to the user. Some people use internet-based applications and some use programs on their
computer to access and store emails.
What is Phishing?
Phishing is a fraudulent attempt to secure sensitive information, such as personal identity and credit card details, while
masquerading as a legitimate operation or individual. Websites that have been ‘hijacked’ for this purpose include PayPal, eBay,
MSN and Yahoo!, to mention just a few. However, hackers can also ‘hijack’ personal email accounts to attempt to trick the recipient
into opening the content. The term ‘phishing’ is derived from the concept of sending mass email to ‘bait’, assuming some will ‘bite’.
What is Spyware?
'Spyware' is a generic term used to describe unauthorised programs that monitor activities on a computer – such as internet surfing
habits and browser activity – through the installation of software without the knowledge or consent of the user. Although
sometimes innocuous, spyware is predominantly malicious. Beyond monitoring computer activity, spyware programs can also
collect various types of personal information and can interfere with user control or alter computer settings.
What is Malware?
Malware is short for ‘malicious software’, and similarly to ‘spyware’, is a term to describe unauthorised programs that are
downloaded to your computer and cause disruption or damage to software or hardware. Sometimes, malware is designed to use
your computer’s ‘resources’ (such as memory) and other times it is simply designed to create an unpleasant experience. Malware
can be accidentally downloaded through spam emails, or when downloading files from untrustworthy websites, such as filesharing websites.
What is Skype?
Skype is a computer program that offers a VoIP ('Voice over Internet Protocol') service. This lets you make calls to people all over
the world via your computers or telephone and have text chats. Calls between computers are usually free, and other Skype calls are
generally inexpensive.
With more than 650 million registered users, Skype is by far the most popular VoIP service, and 'skyping' is now almost as familiar
a term as 'googling'.
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D. Social Networking & Blogs
What is Facebook?
Facebook is probably the best known of the social networking sites. Created in 2004 by Mark Zuckerberg and his friends, originally
as a way for students at Harvard University to get to know each other, it's now believed to have over a billion active users. Some of
its functionality – such as Facebook Connect, a way to sign up to other websites using your Facebook login details – appears across
thousands of other websites.Companies and brands are increasingly building a presence on Facebook, and ‘apps’ such as games
and tools used within Facebook are hugely popular.
Facebook’s key benefits and features
 Facebook is free to join and free to use.
 It can be used by anyone wherever they are in the world as long as they have internet access.
 Facebook users can share messages, video links, photographs and websites.
 Facebook can be used as an organisational tool for planning and managing event invitations.
 You can search by name or email to find people.
 By using various privacy settings, users can choose to allow different people to have access to their pages or to deny them
this access.
 Facebook is available 24 hours a day so people can communicate without time zone differences causing a problem.
What is Twitter?
Twitter is a social networking site that allows people all over the world to comment on news, events and things that are happening
to them as they occur. Known as 'microblogging', these comments – ‘tweets’ – have to be very short.
Twitter’s Key Benefits and Features
 Tweets can be no longer than 140 characters.
 Anyone, anywhere in the world can join in. Users can follow and have access to the opinions of and information shared by
experts, politicians, authors, celebrities and more.
 Comments can be on any subject.
 Tweeters can share comments from other people by ‘retweeting’ them to their own followers.
 Twitter users can choose who they ‘follow’ allowing them to get news and views relevant to them.
 It is possible to remain private on Twitter, by using an alias and/or by locking a Twitter account so that anyone wishing to
follow it must request the right to view the content.
 Twitter users can create lists of other Twitter users, grouped by interest, geography or all manner of other things.
 Tweets can contain links to news items, video and the like on other websites. These links will be shortened automatically
by Twitter.
 Twitter can be used through an 'app' on a mobile phone or hand-held device, through the Twitter website or through
third-party-created software for computers such as TweetDeck.
What is a Blog?
'Blog' is short for 'web log' – basically an online diary or journal created by someone to record in writing their thoughts, feelings or
views on a specific subject or on life in general.
Usually appearing in chronological order, with the most recent post at the top, a blog can be informative, amusing and often
contentious (and sometimes quite tedious). It can contain photographs, cartoons or just text.
It can also have links to other websites or blogs – either ones on similar subjects or ones that are just liked by the blogger and
recommended to anyone interested.
A Blog’s Key Features and Benefits
 Usually written by one person or organisation.
 Is made up of ‘posts’, similar to diary entries.
 Changes regularly.
 Invites visitors to comment or add to the blog.
 Has archives of previous blog posts that can be seen by visitors.
 Can be on any subject.
 Often has extra non-text-based content – for instance, video, art or photographs.
 A list of links to other blogs favoured by the blogger is often present. This is called a ‘blog roll’.
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