Breaking News January 27th, 2007

Types of Computers

1. Personal Computers - made for the individual
   Desktops
   Notebook / Laptops
   All - in - One
   Tablet PC
2. Mobile Computers - can work anywhere
   Cell Phones
   PDAs
3. Internet Appliances - get the information off a network, don't store as much locally
   Web TV
   XBOX
4. Workstations - powerful for companies
5. Servers - make programs and data available for other users through a network
   Clients
6. Mainframes - used to handle large processing jobs
7. Supercomputers - ultra fast that handle trillions of computations a second

What is a Computer?

All computers have input, processing, output, storage, and probably have communications. Together these are called the information processing cycle

A computer, or computer system, is a collection of hardware and software that have been designed to work together.

• Hardware is the physical components
• Software is the programs that run on the computer

• Input : getting your data into the computer

Input is the term used to put the data into the computer. You can use keyboards, mouse, microphone, scanner, etc.

• Data: words, pictures, sounds, numbers, movies, and other things you want to put into the computer
• Processing: transforming the data

Computers only do what you tell them to do. All they can do is carry out step by step operations.

• algorithm - a step by step operation that solves a problem. Programs are made up of different algorithms
  
  • Not all problems are solvable by computers, but scientist are constantly working for new algorithms that will solve previously solvable problems.
  • There are many famous unsolvable problems, NP, NP-Complete problems. TSP, know this from lecture.

The CPU (central processing unit) does all of the step by step calculations. Since the CPU needs to be able to do multiple things at a time, it uses RAM (random access memory) to store the information.

• Output: getting the information to the user

Output is the term used when the computer needs to show the results of the processing. Output devices include a monitor, speakers, and a printer.

• Storage: holding your data for future use

This is when the computer saves the the results of the process so they can be used again later. The processes are in RAM, which is only temporary memory. The computer must store the information onto a storage device for permanent storage.

Storage devices include: hard disk, floppy disc, ZIP disc, usb drive, CD or DVD

• Communications: Moving data between computers

communications is when the computer moves data and information within the computer or between computers. A network is a group of computers that are connected together, usually for the purpose of sharing information.

Communication devices include a modem, wireless card, LAN or Ethernet card

Ethics and Computing

There are many ways to use computers that are unethical. It is up to YOU to use computers the right way. Ways of unethical ways to use the computer include:

• Viruses
• Spyware
• Copying music and movies illegally
• Plagiarism
• Phishing
• Credit Card Fraud
• Spam