CSC 300 Lecture 1 .docx

University of Abuja Faculty of Science Department of Computer Science **CSC 300: Microcomputers Applications** Lecture 1: Computers: An Overview In this lecture, overview of the following topics will be presented: 1. Data and information 2. Simple computer model 3. Hardware components of...

University of Abuja Faculty of Science Department of Computer Science **CSC 300: Microcomputers Applications** Lecture 1: Computers: An Overview In this lecture, overview of the following topics will be presented: 1. Data and information 2. Simple computer model 3. Hardware components of a computer 4. Software components of a computer 5. History of computers 6. Computer applications 7. Mobile devices and mobile applications 8. Computer security 9. Microsoft Word 10. ICT and Society 1. **Data, Information and Knowledge** Data is an unprocessed facts and figures, which at a glance do not have any meaningful interpretation or analysis. Information represent data that have been processed, interpreted in order that it has meaning for the consumer. Knowledge combines information, experience and insight that may be beneficial to the individual or organization. In practice, there is no clear distinction between data and information and there are sometime used interchangeably. Common forms of data are numbers, texts, pictures, audios and videos. Data can either be discrete (countable finite representation) or continuous (non-finite representation, typically in a number line). Numbers are generally used to represents objects (numbers, texts, pictures, audios and videos) and can either by an integer (whole) or floating-point (real with a radix point). Examples: 758 (integer), 9.56 (floating point), 89.0 (floating point), 2.3e-3 (floating point using scientific notation) Depending on the allowable digits, numbers are commonly represented in decimal (base 10, using digits 0,1,...,9, only), binary (base 2, using digits 0 and 1 only), octal ( base 8, using digits 0,1,2,...,7) and hexadecimal (base 16, using digits, 0,1,2,..., 9, A,B,C,D,E,F). Examples: 819 (base 10), 1110011 (base 2), 634110 (base 8) and 0xEA0F (base 16). Note that the prefix 0x is used to represent hexadecimal numbers. Recognizing the relationship between binary and hexadecimal can facilitate easy conversion between two bases. (0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F) in base 16 equal to (0000, 0001, 0010,0011,0100,0101,0110,0111,1000,1001,1010,1011,1100,1101,1110,1111) in binary. Therefore 0xA1C in hexadecimal is equivalent to 101000011100 in binary. 110001010 in binary is equivalent to 0x18A in hexadecimal. 2. **Simple Computer Model** A computer is a programmable electronic device that can store, retrieve, and process data. An algorithm is a sequence of instructions needed to perform a task on a computer. The computer accepts data and instructions, executes the instructions on the data to produce results or perform actions as an output. Conceptually, a computer consists of input, output, processing and storage memory units. The processing unit also called the computer processing unit (CPU) is made of control unit (CU) and arithmetic/logic unit (ALU). The storage memory unit is either volatile ( primary or main memory or RAM) or non-volatile (secondary storage memory). Computers are known for their automation, accuracy, speed, storage capacity, versatility, diligence, multitasking, and communications. To actualize the simple computer model, a computer must need software (logical aspect) and hardware (physical aspect). Software and hardware form the two components of a computer. It is possible physically integrate software into the hardware to form what it is called firmware. A computer can either be digital (accepts binary digits -- 0s or 1s) or analog (works a continuous range of values) or hybrid. Types of digital computers are supercomputers (for high performance computing), mainframe computers (for large organizations), minicomputer computers (less expensive than mainframe and for medium-sized organizations) and microcomputers (general purpose personal computers). Types of microcomputers are desktops, laptops and handheld computers (Personal Digital Assistants). 3. **Hardware Components** Hardware is the tangible or physical parts of a computer: input devices, output devices, memory devices, processing devices Input devices: keyboard, mouse, are joysticks, touchscreens, pen devices, character recognition, voice recognition, barcode readers, universal serial bus (USB) drives, hard disks (HDs) and compact disks (CDs) Output devices: monitor, speaker, printer, headphone. A printer can either be an impact or non-impact printer. Memory devices: volatile -- Read Access Memory (RAM); non-volatile -- Read-Only Memory (ROM), secondary storage devices -- hard drives, DVD/CDs, flash drives The capacity of memory is measured in bytes. 1 byte is equivalent to 8 bits. 1 kilobyte (kb) = 1024 bytes, 1 megabyte (mb) = 1024 kbs, 1 gigabyte = 1024 mbs, etc. Common manufacturers of processing devices (CPU) are Intel and AMD. Examples of CPUs are Intel Pentium, Intel i5 Quadcore, etc. The speed of the processor is measured in hertz (hz is equivalent to one clock cycle -- i.e., time to complete 1 machine instruction cycle). 1 kilohertz = 1000 hz, 1 megahertz = 1000khz, 1 gigahertz = 1000mghz 4. **Software Components** Software is the logical, non-tangible or non-physical unit of a computer. Software are a collection of programs that are used to run a computer. A software is either a system or application software. A system software operates and controls computer hardware and it is either an operating system software or a utility software. Examples of operating system software are Windows OS, Mac OS, Unix/Linux OS, Windows Mobile, iPhone OS (iOS), Windows NT, Android. Examples of utility software are BIOS, virus protection software 5. **History of Computers** The history of computers spans the pre-mechanical era (ancient era), mechanical era, electro-mechanical era and modern era. Ancient era is marked by counting devices, Abacus and tally sticks During the mechanical era, adding machine was discovered by Blaise Pascal (1642), Leibniz (1690). Difference machine by Charles Babbage (1822), Analytic machine by Charles Babbage and Augusta Ada Byron (1833). Babbage is regarded as the father of modern day computers. In the electro-mechanical era, also called the vacuum tubes era, electrically-based computer devices were developed: Herman Hollerith (1890), Howard Aiken (1936), John Atanasoff (1930), John Mauchly and J. Presper Eckert (1946). Modern era is characterized by vacuum tubes and digital computers. This era is classified into generations: first-generation (1943-1958, vacuum tubes, Universal Automatic Computer --UNIVAC, Electronic Numerical Integration Computer-ENIVAC); second-generation (1959-1964, transistors-based computers); third-generation (1965-1970, integrated circuits), fourth-generation (1971-1989, large-scale and very large scale integrated circuits); fifth-generation (1990-present, high performance computing, smart devices, 6. **Computer Applications** During the past few decades, computers and electronic technologies have been incorporated into almost every aspect of society. Areas of applications include, but not limited to, business, banking and finance, government, education, marketing, insurance, healthcare and medicine, engineering design, military, home, manufacturing, agriculture, workplace, scientific research, recreation and entertainment. 7. **Mobile devices and applications** Mobile computing is the next evolution in the development of computing systems. Mobile Computing is the use of portable computing devices (such as laptops, tablets, smartphones) in conjunction with communication technologies that allow transmission of data, voice and video usually over a wireless network. The following wireless networks support mobile computing: Wireless Personal Area Networks (Bluetooth, Sensors, etc.); Wireless LANs (802.11 family); Fixed Wireless (e.g. CDMA); Cellular networks - 1G to 5G; and Satellite systems. Mobile hardware: portable laptops, smartphones, tablet Pc\'s, Personal Digital Assistants. Mobile operating systems software: Android (from Google), iOS (from Apple Corp.), Blackberry OS (from RIM), Windows Mobile (from Microsoft). Mobile Communication Technologies: 1G-5G -- first to fifth generation mobile telecommunication; global positioning system (GPS); long-term evolution (LTE), Worldwide Interoperability for Microwave Access (WiMAX); and Near Field Communication (NFC). 8. **Computer Security** Computer security involves the process of protecting assets to ensure confidentiality, integrity and availability. Confidentiality implies that only authorized users can view assets; integrity implies only authorized users can modify assets; and availability implies authorized users are able to use and have access to assets Control measures for confidentiality include access control, authentication and identification. Identification is the action or process of asserting one's identity. Authentication is the act of establishing or confirming that one actually is who he or she claims to be. A commonly used authentication method is password. A password is an agreed-upon word, phrase, or set of characters that is presumed to be known only by the user and the system. Strong authentication Something the user knows, e.g., password, PIN, mother's maiden name, etc. Something the user has, e.g., physical key, ID badge, driver's license, security token, etc. Something the user is, e.g., voice recognition, biometrics Combining two or more of these authentication mechanisms strengthens the authentication process (multifactor authentication) Best practices for securing assets: Educate yourself. Organizations provide internal security training for all employees. Be skeptical. You should treat anything you see online with a high degree of skepticism. Check privacy policies & settings. Make sure you understand them, as they likely if your information is shared with other parties. Good passwords. Use good, strong passwords. If possible, the password should contain letters and numbers, as well as special characters. Protect the password. You should never share your password with others. Stay updated. Always ensure that the software you use is up-to-date. 9. **Microsoft Word (Brief)** Microsoft Word is an example of a Word Processor. Word Processors are used for word processing, that is, used for creating and editing text based documents such as memo, letters, newsletters, minutes, projects etc ). Microsoft Word belongs to a group of Microsoft applications called Microsoft Office suite. Others include Microsoft Excel, Microsoft Access, Microsoft PowerPoint, and Microsoft Outlook. Microsoft Word has features for: - Automatically pointing out misspelled English words by underlining them, - Automatically pointing out grammatical English error by underlining them, - Formatting Documents automatically as you type, - Keep track of changes made to your document etc. 10. ICT and Society Today, Information and Communications Technology (ICT) has become an integral part of the human life. The Internet and the social media have come to completely revolutionize the human life and activities. The internet may be simply defined as a global communication network that allows almost all computers worldwide to connect and exchange information. Internet services include: - World Wide Web (WWW) - Electronic Mail (E-mail) - News Groups - File Transfer Protocol (FTP) - Internet Relay Chat (IRC) - Telnet - Voice over Internet Protocol (VoIP) - Gopher Social media is comprised of online communications channels dedicated to community-based input, interaction, content-sharing and collaboration. Websites and applications dedicated to forums, microblogging, social networking, social bookmarking, social curation, and wikis are among the different types of social media. Presently, there are hundreds of social media platforms in existence and operation. Some of them are: Facebook, Google+, Friendster, hi5, LinkedIn, Twitter, Tumblr, XING, Flickr, Howcast, iTunes, MySpace, Picasa, Vimeo, YouTube, Blab, Delicious, Digg, Instagram, Pinterest, Quora, Reddit, Scribd, SlideShare, Wikipedia, Yelp, WhatsApp, 2Go, Nairaland, LindaIkejiBlog, etc.