Today 29 aug 2016 is the first day of my semester 2 and the first subject is computer application.Our computer application lecture is friendly to us and she asked us about what is computer and telling us. 

   
Chapter 1

   What is a computer

1.  A computer is an electronic device,operating under the control of instructions stored in its own memory.
2. It will collects data(input),processing and produces information(output).

  The components of a computer

• A computer contains many electric,electronic,and mechanical components known as hardware

1. Input device-allows you to enter data and instructions into a computer.
2. Output device-hardware component that conveys information to one or more people.
3. System unit-case that contains the electronic components of the computer that are used to process data
4. Storage device-record (writes) and/or retrieves (reads) item to and from storage media.
5. Communications device-enables a computer to send and recevive data,instructions,and information to and from one or more computers or moblie devices.

Advantages and Disadvantages of Using Computers

Advantages of using computer

• speed
• reliability
• consistency
• storage
• communications

Disadvantages  os using computers

• health risks
• violation of privacy
• public safety
• impact on labor force
• impart on environment

Green computing involves reducing the electricity consumed and environmental waste generated when using a computer

Strategies include:

-Recycling

-Regulating the life of computers

-Extending the life of computer

-Immediately donating or properly disposing of replaced computers

Networks and the internet

• A network is a collection of computers and devices connected together,often wirelessly,vsa communications devices and transmission media.
• The internet is a worldwide collection of networks that connects millions of businesses,government agencies,educational institutions,an d individuals.

• People use the internet for a variety of reason:

       -communicate 

       -research and access information 

       -shop

       -bank and inverst

       -online trading

       -entertainment

       -download videos

       -share information

       -wed application

• A social networking web site encourages members to share their interests, ideas,stories,photos,music,and videos with other registered users.