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COMPUTER
APPLICATION
Definition
COMPUTER: a computer is an electronic device that inputs and store data.
-is an electronic device which accepts data/ information, processes it, stores the result, an give the output as per the users instruction. Meaning that the computer can not function unless it is commanded or instructed. (GIGO) garbage in garbage out.
- The computer can be categorized in to two or four parts
- Hardware
- Software If you are told to mention four then you add the following -Input -output -processing -storage
- For hardware devices to function they require instructions meaning the hardware can not function without the software.
HOW THE COMPUTER WORKS; the computer work when given instructions from the user the instructions initiate four major operation of the computer which are input operation, processing operation, storage operation and output operation. Meaning that accepts the data, then it process it and saves it, then it stores it again.
PARTS OF THE COMPUTER
The computer is made of two major parts
- HARDWARE
- SOFTWARE -HARDWARE: this is the part of the computer which we can see and touch ( tangible), the hardware parts of the computer are grouped into different categories or groups basing on the operations they perform, that is to say all the hardware which perform related or similar tasks are grouped into the same group.
FOUR DIFFERENT CATEGORIES
- Input devices or input unit: this deals with entering information or data into the computer. They do convert data from the format that is understood by human beings to the format that is understood by the computer.
- Example a
- microphone what does it captures the voice that human beings, the computer captures electronic signals.
- (^) Biometric device
- Keyboard
- Electronic drawing devices
- Joy stick; used for entertainment and navigation
- Bar code reader
OUPUT DEVICES ;these are devices that receive information from the computer and takes it out to the users. They usually convert data/ information from a format that is understood by the computer that is understood by human beings. -Printer -speaker
-Logical operators- OR, AND,NOT(NEGATION),NOR< NAD,XOR
OR- this is used where two or more tasks of the same priority requires execution, it means the computer decides by using the OR operator meaning task A OR task B, meaning any of the two can be executed before the other. AND- this means that task A and B are used simultaneously NEGATION-this means opposite of this is used to reverse.
NOR-are used only when previous decisions were made with the help of not and and or
NAND; means NOT task A and Task B, meaning that the tasks will stop
XOR- meaning no right answers
STORAGE UNIT/STORAGE DEVICES
There are two storage devices primary and secondary devices
PRIMARY STORAGE: involves RAM,ROM and Hard disc drive.
SECONDARY STORAGE: involves memory sticks, compact disc, external hard drive and floppy disc
It include random access memory RAM, hard disc drive (HDD) and Read only memory( ROM).
RANDOM ACCESS MEMORY(RAM): the ability to transfer information of Ram is faster then the hard disk drive. The term random refers to the frequently communication that is made between the memory and the processor (CPU). Ram stores data on temporary basis that is to say it is a temporary storage device. The information/data that is stored within RAM get lost when power goes off, thus it is referred as VOLATILE (means it is easily evaporates) memory
TYPES OF RAM
- (^) SD RAM
- DD RAM
HARD DISC DRIVE: This is the largest storage device within a computer, which also determines the speed of the computer. The hard disc is usually partition into different partitions (BLOCK) which use letters followed by colons to denote the names of the portions for eg, D:, C:,G:, etc. N.B the hard disc is a magnetic storage device in nature this means that it can be attracted by iron.
READ ONLY MEMORY (ROM): means accessing information that are in the device. This memory does store the bootable files of the computer. The said files are entered into the memory during the manufacturing of the computer once the files have been entered the memory will not allow more files to be entered even if space does prevail (exist) so it is referred as “Write Once Read Many Times” kinds of memory ( WORM) this describes the nature of the device, once the info is entered you can not add more or delete the entered info.
- (^) Malware are programs which are made with the purpose of destructing the normal computer operation - the very first malware was developed by the Pakistan brothers, these brothers went to china to sell their software in an inetrational exbition , they sold the product and in two weeks the Chinese made another software and sold it cheaper, so the 2 brothers went back to Pakistan and came up with an idea. - (^) COMPUETR VIRUSES Refers to the program which enters to the computer with or without the knowledge of the user and destruct the normal computer operation
CHARACTERISTICS
- Virus spread by attaching themselves to a host file
- They replicate, this is their mode of reproduction.
TYPES OF COMPUTER VIRUS
- Companion virus: this is a kind virus that attaches itself to each and every program of the computer, and initiate their operations from time to time. The tendency continues until the computer memory is saturated thus the computer comes to a hault.
- Directory virus: is the kind of virus that enters to a computer and goes on the logbook and it changes the location addresses within the hard disk, this virus changes the address of the different programs located within the hard disk, when the computer tries to locate the program in the hard disk fails because the wrong address of the program location has been put, it also creates its own directories.
- (^) Macro virus: these are viruses which automate repeated tasks.
- (^) Logic bomb: this is a computer virus which enters into the computer and remains inert until certain conditions are met.
TYPES OF MALICIOUS SOFTWARE
- VIRUS
- WORM: these are like computer virus except that they do not depend on a host so as to spread. They hop from one computer to the other. They mostly attack the communication channel of the computer network thus causing traffic jam, these are programs which attack the ports of communication. CHARACTERITICS OF WORM
- They replicate like computer virus
- They hop from one computer to another
- TROJAN HORSE: these ae safe in nature but they carry dangerous harmful programs in them, they easily bypass computer security check points.
COMPUTER NETWORKS
The file is being transmitted from the source to the destination without being broken down into smaller packets. For example using whatsapp. Protocol is a software that establishes a link. It simplifies communication.
- TCP / IP TRANSMITTION CONTROL PROTOCOL/INTERNET PROTOCOL: transmission control protocol it deals with: Ensuring that data is broken down into packets. Every packet is given 2 addresses sender’s and receiver’s address. The internet protocol deals with establishing of the communication network (route) NOTE: upon reaching the destination packets are rearranged in a correct order and during transmission the packets are encrypted (coded). IP brakes down the the packets.
-SIMPLE MAIL TRANSFER PROTOCOL SMTP: it deals with transmission of electronic mail.
-HYPER TEXT TRANSFER PROTOCOL (HTTP): the function of this is to deal with the transmission of web content which we refer to whatever content that come up on the page of the website or browser, it arranges those contents that you see. If it fails then contents will be dis organized.
- CONNECTING DEVICES: these are devices which help to connect one communication channel and the other, a communication channel to the Pc e.t.c TYPES OF CONNECTING DEVICES
-HUB: was the 1 st^ connecting device to be developed, it can connect up to 8 computers only.
HOW DOES THE HUB WORK?
A hub works by broadcasting meaning that it works when 2 computers wishes to communicate information from the sender is duplicated depending on the number of computers that are connected to the hub. Upon completion the duplicated copies are sent out to all the computers that are connected to the hub. After receiving the information, the receiver will accept the information if the address on the information packet matches its own address otherwise the information is rejected and discarded. Read about switch repeater and router
DRAWING OF HUB
ADVANTAGES OF HAVING COMPUTER NETWORKS
-Sharing of the resources -facilitates communication through network (internet) makes it possible for video calls and audio calls famously known as voice over internet. Example skype.
- it saves time example emails
DISADAVANTAGE OF HAVING COMPUTER NETWORKS
- Malware: this is a computer virus meaning it is also a crime. The creation and usage of malicious software to cause any illegal action such as sabotage it’s a crime.
- Internet fraud; this is the same like a computer fraud where by it intends to help execute an illegal scheme with the intent to damage it.
- Stealing identities;
- Cyberstalking
A Router: this is the most intelligent connecting device its main function is to connect a computer to the internet by identifying and establishing the path/ route from the source to the destination. It does so by using two algorithms
- Shortest time first:
- Shortest path first:
- There is a drawing here, make sure to check it out on Harry’s note book.
- In that drawing the lines represents channels of communication
- The dots represents Nodes
- There are four possible routes
- Working time: this is the time the information takes to get there
MODERM: modulator and demodulator gives us modern. its function is to convert analog signal to digital signal and vice versa.
- Round angels represent analog signals
- Square angels represent digital signals
The information that coms from the Vsat is in analog then it gets converted into digital and when it is getting
out from the modern to the VSAT it becomes analog again.
VSAT: this is like a dish that catches wave and sends them
SWITCH, ROUTER AND PC: are digital devices meaning that it does not work with analog
REPEATER: the main functions is to rejuvenate the signals under transmission. BRIDGE: this is used to break down larger networks into smaller sub divisions.
nd
SEMESTER
topics:
- Microsoft office word 2007
- Microsoft office excel 2007
- Microsoft office power point 2007
- Microsoft office access
- Introduction to windows 10 (this is for people who will sign for it only) meaning it aint in the syllabus
MICROSOFT OFFICE PACKAGE 2007
The Microsoft office package does contain a list of application programs which are meant to perform office operation.
- MICROSOFT OFFICE WORD 2007: This is sometimes referred to as a text editor meaning it deals with text formatting that is changing font size, font color, font style etc. NB; a rich text refers to images and normal text is a simple text meaning black and white text.
ADVANTAGES OF MICROSOFT WORD
- Correction can be done easily,
- Print as many copies,
- storage for future use,
This is an application program that helps in project management.
PROJECT MANAGEMENT: this refers to project initiation then project planning.
PROJECT INITIATION: different ideas that a person gives so as to start a project. There is brainstorming of the idea.
PROJECT PLANNING: involves
- (^) Capital
- Labor force
- Time SCHEDULING: planning on how to use the capital. TASK SCHEDULING: assigning different tasks to the people.
- It assists individual to do scheduling of capital
- Scheduling of labor force
- Scheduling on the time
MICROSOFT WORD OFFICE 2007
FEATURES OF SCREEN
- Tittle bar (shows the name of document) It has the function to display the title of the document by default the computer gives “Document 1”.
- Office button: it has the function display shortcuts to different operations example New, Print etc.
- Quick access tool bar: the function of the quick access tool bar is to display shortcuts or icons of frequently repeated tasks, it can be displayed and hidden as well as change the icons that are within they can be added or removed.
NB: the icons of the operations within the quick access tool bar can be added or removed by clicking on the down ward pointing arrow within the access tool bar
There is a drawing here::
- Ribbon: this is a collection of tabs Home (home tab)
- Tab: is a collection of different groups. Group(s) is a collection of icons leading to related tasks ( these are used interchangeably)
- Horizontal ruler: a ruler is used for scaling factors ( it is not visible) if you want to make it visible you go to view tab and click ruler.
- Vertical Ruler: this is find on the left side of the Microsoft word screen and it is also for scaling purposes ( you go to page layout and page setup click the arrow going down)
you click on that box. On the left part where the box is longer its called font style
STEPS FOR CHANGING FONT STYLE:
i. Same as above ii. Same as above iii. Select font style on the icon iv. You click on on the little arrow pointing downwards Example Times New Roman or Impact, cosmic and Arial
STEPS FOR CHANGING FONT ORIENTATION
i. Same as above ii. Same as above iii. Select /click orientation icon for italicizing texts /
- PARAGRAPH FORMATING: these are different formats that are performed in the entire paragraph on its totality and not individual texts within the paragraph
i. Paragraph alignment: this refers to arrangements of lines within the paragraph. TYPES OF PARAGRAPH ALIGNMENT
Alignments refer to the arrangements of lines in paragraph,
i. Left alignment: refers to the arrangement of paragraph lines such that all the lines of the paragraph touches the margin (left margin) but may not necessarily touch the right margin.it must touch the left margin.
ii. Right alignment: all lines must touch the right margin but may not touch the left margin.
iii. Center alignment: the lines of the paragraph are centered between the 2 margins.
iv. Justify alignment: the lines of the paragraphs are stretched such that they touch both of the margins.
STEPS FOR APPLYING THE DIFERRENT MARGINS
i. 1 st^ highlight the item or paragraph ii. go to home tab iii. select the icon for
LINE SPACING: this is adjusting the space between lines of the paragraph
i. highlight the paragraph ii. go to home tab iii. select line spacing icon
BULLETS AND NUMBERING:
i. highlight the paragraph ii. you go to home tab iii. then you select bullets iv. and the numbering is also the same
INDENTATIONS: refers to the gap between the lines of the paragraphs and the margins There are 4 different type
i. Left indentation: the gap is on the left of the paragraph. ii. Right indentation: the gap is on the right of the paragraph iii. First line indentation`; the first line leaves a gap. iv. Hanging indentation:: the lines start from the left to the right margin touches both margins and the rest of the lines touch only 1
STEPS TO GET FIRST LINE AND HANGING INDENTIFICATION
i. Expand the paragraph group by clicking on the corner arrow ii. Go to special iii. Select hanging / first line
ADJUSTMENT OF INDENT
i. Highlight ii. Go to home tab
