Internet is a network of all computers all over the world.
To connect to the internet you need 4 things :
A computer system
A modem
A telephone line
An internet service provider ( In short ISP)
What is a modem?
Is a hardware which the computer is connected to the internet via the telephone lines / cable.
Converts from digital signals to analogue signals .
What is an ISP?
An internet service provider is a company with whom anybody wanting to connect to the internet has to be able to do so. Eg of an ISP are go, onvol , nextgen and much more.
What is a web browser?
world wide web is the most popular part of the internet. Contains many information. When you search information you use a special programm called web browser. It displays web pages from any computer on the web . |The browser converts the special HTML ( HyperText Markup Language ) codes that are used to create a web page .
Type of web browser - Mozilla fire fox.
What is a URL?
It's short word for uniform resource locator
What is a search engine?
With a search engine you can type keywords and it will search through all the webpages around the world and give you a list of sites (hyperlinks) that match it so that you can jump directly to that page .
Hi so today we have another topic to discuss about . The topic is called spreadsheets.
It is a program that is used to procesd number and calculations . It is mainly used for automatic calculations. A cell may contain 3 different terms called : Label- a heading or titled for a row / column
Value -a number a formula used to perform different calculations Formula - used to perform calculations on cells containing values. IMPORTANT TOOLS TO REMEMBER !! Insert rows and coloums - a new coloumn is inserted in front of the coloumn that is highlighted.
Input device is any hardware component that allows a user to enter data .
Keyboard
Application-word processing
It contains keys that allows you to enter data and instructions into the computer. We all know that Many desktop computers have the numeric keyboard that is on the right side of the keyboard. A standard keyboard is known as QWERTY KEYBOARD because of the layout of it's typing area which is similar to that of a type writer.
Advantages- It is faster than a pointing device
Disadvantages - it takes a lot of time to practice in order to type quickly
Mouse
Application- Menu selection
It is the mouse widely used pointing device. A mechanical mouse has a rubber ball on it's under side to detect movement of the mouse. An optical mouse uses a device that emit and sense the light to detect the mouse's movement.A cordless mouse transmits data using wireless technology such as radio waves or infrared lights.
Advantages- A mouse is easy and convenient to use a graphical interface
Disadvantage- It is not easy to input text with a mouse.
Magnetic Reader
Aplication- used by banks
It can read text printed with magnetised ink. It is most used by banks for processing cheques.
Advantage-Difficult to forge. Documents can be read when folded or written on.
Disadvantage- Reads and encoders are very expensive. Can only accept a few different characters set.
Scanner
Application- Converting a hardcopy to a machine readable form
A scanner is a light sensing device that converts printed text and graphics into a digital form that can be further proccesed by the computer.
Two popular types of scanner are:
Flatbed scanner -works like a copy machine exept that t creates a file of the document rather than a paper copy.
Handheld scanner
This can be passed over the image to be scanned. These are ideal for capturing small images such as signatures and logos. These are used for image processing too.Contains OCR
.
Advantages- Using appropriate software you can edit pictures and insert them in the document.
Disadvantage-A scanner is best for two-dimensional objects only.
OCR-Optical character recognition
Works in conjunction with word processirs . It converts an image of text into a text file that can be edited.It uses a scanner to read an image and compares that image with a set of characters patterns that are stored in the computers databases
Advantages-hard copy can be read directly into the pc without re typing. The characters that are converted can be edited later.
Disadvantage-They often do not work well with handwritten characters or those in unusal fonts.
Coloumns- are mainly used in newspapers and magazines Mail Merge-It is used to do personalised letters by combining together a form of letters and a list of data . Table of contents-is a list of heading in a document. You can use a table of contentsto get an overview of the topics together with their page number. Indexes-An index list th terms and topics dicussed in a document, along with the page number.To create it you need to mark the index apperaing in your document.
Viruses are small programms that may harm your computer. You can have a virus from internet or a drive . An antivirus software server is needed to protect your computer from viruses . The most common antiviruses are Mac A fee and norton anti virus.
