CLASS IX

Ø TCP/IP – Transmission Control Protocol / Internet Protocol  Ø SMTP – Simple Mail Transfer Protocol  Ø POP3 – Post Office Protocol 3  Ø HTTP – HyperText Transfer Protocol  Ø HTTPS - HyperText Transfer Protocol Secure  Ø FTP – File Transfer Protocol  Ø TELNET – Telecommunications Network  Ø SFTP: Secure File Transfer Protocol  Ø PPP: Point to Point Protoco  FTP : FTP is used to transfer large files. It is often used for organising files on a web server for a website. You can have private access to an area on an FTP server where you can upload your files. You can then give another user access to download the documents that you have shared.  Ø SFTP: It is the secure version of File Transfer Protocol (FTP).  Ø HTTP : HTTP transfers web pages from web servers to the client. All web page addresses start with http. An https address is a secure web address which has been encrypted. An https address is used for sites holding bank detail...

 INPUT DEVICES: The devices through which we enter data and instructions are called Input devices. Examples:  Keyboard: It is used to input data and instructions into the computer. A standard keyboard has 104 keys which are divided into four groupsTyping keys, Function keys, Navigation keys and Control keys. Sir Christopher Latham Sholes was the inventor of QWERTY keyboard. Joystick-It is a device used to control cursor on screen. Normally it is used in Games and specially designed simulation software. Barcode reader:- It is used to accept barcode inputs. A barcode is a series of vertical bars representing numbers and alphabets printed on product labels. One must have noticed all standard items like perfumes, greeting cards, books, cassettes available in the market have similar lines as shown in the figure, known as bar codes. These can be read with the help of bar code readers.  Mouse: It is a hand-held pointing device. It is used to control the movement of the pointer to se...

 Q1. Write the full forms of  a. PDA  B. DVD Q2. What are registers? Q3. Write short note on Mainframe computers? Q4. Explain types of computer according to principle of operation wise? Q5. Identify the category of computer a. Computer in offices, school computer lab b. Portable computers c. Most powerful computers d. Computer also known as mid rage servers

 1. Internet- Internet is a global network of computer networks that enables information to be exchanged. In internet, most computers are not connected directly to the internet. Rather they are connected to smaller networks, which in turn are connected through gateways to the internet backbone. Internet is not governed by any particular body. It is coordinated by many volunteer organizations.  2. Advantages of Internet-  • Greater access to information reduces research times.  • Useful communication links  • Global reach enables one to connect to anyone on the internet.  • Easy communication with other people.  • Publishing documents on the internet saves paper.  3. Disadvantages of Internet-  • Cyber frauds may take place involving credit/debit card numbers and details.  • Computer viruses get downloaded and spread across machines connected to networks and have detrimental effects. World Wide Web (WWW) - www is a set of progra...

 Computer System (chap-1)  1. Computer- A computer is an electronic device that can perform a variety of operations according to a set of instructions called program 2. Hardware- Hardware refers to physical parts of the computer that can be touched physically. 3. Software- Software refers to the instructions that tell the computer what to do 4. Data- Unprocessed raw facts and figures are data e.g., a name (Ram), some marks (72.5%), a year (2020) etc. are data. 5. Information- It refers to the processed data that is meaningful e.g., above data can be converted into information as “Ram, who passed in 2020, secured 72.5% marks.” 6. Functional components of a computer system A computer, mainly, has four functions 1. Accepts data- data 2. Processes data- Processing 3. Produces Result/Output- Output 4. Stores Results- Storage Convergence of technology is the interaction of two or more different technologies in a single device or system. eg. ICT, Smart phone, mobile tv etc....