Femtech Information Technology

Networking and Network Topology for SS3 Definition of Network and Networking A computer network consists of a collection of computers, printers and other equipment that are connected together so that they can communicate with each other. It is also defined as a group of two or more computer systems linked together. Computer Networking is the scientific and engineering discipline concerned with communication between computer systems. Types of Network Network can be grouped into three categories, namely; A. By Scale B. Topology C. Functional Relationship Types of Network According to Scale Depending upon the geographical area covered by a network, it is classified as: 1. Personal Area Network (PAN):  PAN is a computer network organized around an individual person (typically within 10 meters). PAN may be wired with computer such as USB and Fire wire. A wireless Personal Area Network (WPAN) can be made possible with network technology such as infrared Data Association (irDA) and Bluetooth.

Network Cables and Connectors for SS3 Definition of Network Cable Network Cables are medium through which information usually moves from one network to another. Types of Network Cables The following are the types of cables used in networks: a. Unshielded Twisted Pair (UTP) Cables b. Shielded Twisted Pair (STP) Cables c. Coaxial Cables d. Fibre Optics e. Telephone Unshielded Twisted Pair (UTP) Cable UTP is a popular type of cable that consists of two unshielded wires twisted around each other. Due to its low cost, UTP cabling is used extensively for local-area networks (LANs) and telephone connections. UTP cabling does not offer as high bandwidth or as good protection from interference as coaxial or fiber optic cables, but it is less expensive and easier to work with. Shielded Twisted Pair (STP) Cables Shielded twisted pair is suitable for environments with electrical interferences; however the extra shielding can make the cables quite bulky. Coaxial Cable Coaxial cabling has a sing

INTRODUCTION TO WWW for SS3 Meaning and Definition of WWW WWW (World Wide Web) is part of the internet that contains linked text, image sound, and video documents. It is also define as an information space where documents and other web resources are identified by URLs, interlinked by hypertext links, and can be accessed via the Internet. Brief History of WWW In 1989, London born Timothy Berners-Lee came up with the idea of the web as a way to share files with others. The idea for the web came while Berners-Lee was working for the European Organization for Nuclear Research (CERN). Scientists by trade, Berners-Lee and others inside CERN were looking for ways to transmit information between each other electronically. To do so, they created a set of tools including a language (html), a browser and other utilities which allowed them to establish communication. The first web browser was invented in 1990 by Sir Tim Berners-Lee. His browser was called WorldWideWeb and later renamed Nexus. Many

Electronic Mail (E-mail) for SS2 Definition of Electronic Mail Electronic mail, commonly called email or e-mail, is a method of exchanging digital messages from an author to one or more recipients. It can also be defined as a system for sending and receiving messages electronically over a computer network. E-mail Services The following are services provided by email 1. Sending/receiving emails 2. Chatting : The exchange messages online in real time with one or more simultaneous users of a computer network 3. Task List : Task is a feature designed to help you keep track of the things you need to do. 4. Share updates, photos, videos and links. Steps to Create Email Account Follow the steps below to create email account 1. Click On a web browser 2. Visit a website that offers an email service e.g. www.gmail.com 3. Click on the Free Sign Up Button 4. Enter all mandatory fields (First Name, Last Name, Gender, etc.) 5. Click the "Accept" - Button underneath Email Address An email a

        Internet for SS2 Definition of Internet Internet is a worldwide network of computers that share information. It is also defined as a global system of interconnected computer networks that use the Internet protocol suite to link devices worldwide. Internet Terms 1. Cyber café : An internet café or cyber café is a place which provides internet access to the public, usually for a fee. 2. Cyber space : It is the electronic medium of computer networks, in which online communication take place. 3.  URL  : To transfer a file from remote computer to a local computer. In other words, it means to transfer a file from a web server to a web client. 4. Upload : Transfer a file from a local computer to a remote computer. In other words, it means to transfer a file from a web client to a web server. 5. Email : E-mail is mail that's electronically transmitted by your computer. 6. File Transfer Protocol (FTP) : FTP is the standard method for downloading and uploading files over the Inter

BASIC Programming II (Built-in Functions) for SS2 BASIC built in functions are predefined functions that performs a wide range of operation. A function is a structure that simplifies a complex operation into a single step. BASIC has a number of built-in functions that greatly extends its capability. They include the following: 1. SQR Function : The SQR function calculates the square root of a number. The general form of the function is SQR(X) Example : SQR(9) = 3 SQR(2) = 1.414214 2. INT Function : The INT function finds the greatest integer less than or equal to a number. The general form of the function is INT(X) Example INT(15.46) = 15 INT(-15.46) = -16 INT(15.56) = 15 INT(-15.56) = -16 3. CINT Function : CINT means Integer Conversion. This function is used to convert a number into an integer. It rounds off the number to the nearest integer value. Example CINT(15.46) = 15 CINT(-15.46) = -15 CINT(15.56) = 16 CINT(-15.56) = 16 4. Fix Function : This function truncates the number int

Algorithm and Flowchart for SS2 Definition Algorithm Algorithm can be defined as the set of rules and sequential steps that define how a particular problem can be solved in finite and ordered sequence. Function of Algorithms An algorithm generally takes some input, carries out a number of effective steps in a finite amount of time, and produces some output. Characteristics of Algorithms Every algorithm should have the following five characteristic features 1. Input 2. Output 3. Definiteness 4. Effectiveness 5. Termination Example1 : Write and algorithm to compute the area and circumference of a cycle given the diameter d. Use the formular Solution Step 1: Start Step 2: Get the diameter d Step 3: Compute Step 4: Compute Step 5: Compute Step 6: Display the results Step 7: Stop Example 2 : Write an algorithm that tells you how to wash dishes Solution Step 1: start Step 2: scrape food off dishes Steps 3: wash the dishes with soap and water Step 4: Rinse the dishes Step 5: Dry them Ste

Program Development for SS2 Definition of Program A program is a set of instruction that is executed by the CPU. A program can also be defined as an organized list of instructions that, when executed causes the computer to behave in a predetermined manner. Without program the computer is useless. Characteristic of a Good Program The following are characteristics of a good program. Accuracy : Program should be sufficiently accurate to get the desire results. Extensibility : this means that you so design your program that you can add and remove element from your program without disturbing the underling structure of the program. Maintainability : this is making your code easy to update Efficiency : a good program should be designed to use the least amount of primary memory and the fewest devices possible. Generality : Design the program to be generalized and flexible, if possible Portability : a good program can be moved to another environment Simplicity : program logic should be as si

System Development Life Cycle (SDLC) for SS2 Definition and Description System Development Life Cycle 1. System development Life Cycle (SDLC) is a conceptual model in project management that describes the stages in an information system development project. 2. The system development life cycle can be defined as a project management technique that divides complex projects into smaller, more manageable segments or phases. A system development life cycle has three primary objectives: To ensure that high quality systems are delivered, to provide strong management controls over the projects, and to maximize productivity of the systems staff. Stages of System Development Life Cycle The following are stages of system development life cycle a. Preliminary study b. Feasibility study c. Investigative study d. System analysis e. System design f. Implementation g. Maintenance h. Study review Diagram of System Development Life Cycle Description of each Stage Preliminary study The initial system

Computer Data Conversion for SS2 Data Conversion : Data conversion is the conversion of computer data from one format to another. Registers : Registers are temporary storage areas for instruction or data. It can also be defined as a special, high-speed storage area within the CPU. They are not part of the memory; rather they are special additional storage locations that offer the advantage of speed. Register works under the direction of the control unit to accept, hold and transfer instruction or data and perform arithmetic or logical comparison at high speed. Register are the fastest memory available for use in the PC, because they are hard-wired right into the processor logic. Address: A memory address is an identifier for a memory location, at which a computer program or a hardware device can store data and later receive it. Bus: A bus, in computing, is a set of physical connections (cables, printed circuits, etc.) which can be shared by multiple hardware components in order to comm

Central Processing Unit for SS2 Brief history of the CPU The fourth generation computers started with the invention of Microprocessor. The Microprocessor contains thousands of ICs. Ted Hoff produced the first microprocessor in 1971 for Intel. Definition of the CPU The Central Processing Unit (CPU) also known as the microchip or the microprocessor (or processor for short) is the electronic circuitry within a computer that carries out the instructions of a computer program. This is the brain or heart of the computer. The main objective of the CPU is to perform mathematical calculations on binary numbers. Most modern CPUs are microprocessors, meaning they are contained on a single integrated circuit (IC) chip. Some computers employ a multi-core processor, which is a single chip containing two or more CPUs called "cores". Components of the Central Processing Unit The central processing unit consists of two parts: 1. Control Units (CU) 2. Arithmetic Logic Unit (ALU) The Contro