1. CIT 1100

2. The evolution of the computer:  The first known device used to assist with mathematical calculation was the Abacus developed around 3000 BC  In 1617, John Napier created a mechanical calculator; referred to as Napier ’s bones it was a crude slide rule  In 1672, Blaise Pascal developed the first mechanical adding machine, capable of addition only  In 1822, Charles Babbage created the Difference Engine which is touted to be the first general purpose computing machine

3. Replica of Charles Babbage’s Difference Engine The London Science Museum Based on the decimal number system and was powered by cranking a handle

4.  The first devices were designed to assist with mathematical computations  All were mechanical, large, slow and cumbersome  Capable of precise error free calculations  Based on decimal numbering system

5.  Personal computers (PCs)  Desktop computers  Notebook (laptop) computers  Tablet PCs  Handheld computers  PDA (personal digital assistant)  MP3 players  Mainframe computers  Supercomputers

6. Special Purpose Devices  Every automobile built since 1995  Airplanes  Boats  Mall lighting systems  Home security alarms

7.  Music  Visual Art Extremely powerful Supercomputers are used to create modern 3-D models used in animation, games and military simulations The Graphic Arts industry has changed dramatically through computers as well

8.  Banking ◦ On-Line banks ◦ Credit Cards ◦ ATM Machines  Retail Sales ◦ Book Stores are being replaced by on-line sales  Amazon Kindle  Digital Print Media  Internet Commerce increased from $500 million in 1996 to over $6 billion in 2000  Any individual with a Web Site can compete with a multinational corporation

9.  Games  Today, many of us regularly play computer games on the Internet that enable us to talk run, and explore with people all over the world at the same time  Interactive game play can incorporate players from all over the world  Computing devices have transformed modern life in ways too numerous to list

10. Computers are basically machines, made up of dif­ ferent components -  A modern computer consists of three major components:  A modern computer consists of three major components: 1. Hardware ◦ Physical thing that you can touch or hold in your hand 2. Operating system ◦ Controls the hardware and enables users to interact with the computer (interface) 3. Applications ◦ Programs that allow you to do specialized tasks

11.  Computers work through three stages:  Computers work through three stages: 1. Input 2. Processing 3. Output

12. The user initiates the action by doing something: ◦ Clicking the mouse ◦ Typing on the key­ board ◦ Touching the touch screen This is input

13. Components inside the system take over at that point - The operating system instructs the hardware how to handle your request At the heart of every computer is a central processing unit (CPU), usually a single, thin wafer of silicon and millions of tiny transistors The CPU handles the majority of the processing tasks and is the "brain" of the computer The CPU handles the majority of the processing tasks and is the "brain" of the computer

14.  Once the computer has processed the request, it shows you the result by changing what you see on the monitor or playing a sound through the speakers  This is output

15. There are nine steps that apply to most computers and computing devices when you want to get something done 1. Power up 2. Processing parts prepare for action 3. User provides input 4. Input commands are processed 5. CPU send output information to your output devices 6. Output devices show you the results 7. Repeat steps 3-6 until complete 8. Save your work 9. Power down the computer

16.  Computers have a piece of hardware called a power supply that plugs into some kind of power source, like an AC outlet on a wall  Once power is applied the power supply delivers voltage to system components to initialize them

17. The power supply connecting to devices

18. The Power Supply is vital to the operation of many components inside the system -  If there is a problem it can effect the system in many ways ◦ If the power supply is completely dead obviously the entire system would not operate ◦ If the required voltage levels expected from the power supply were incorrect it can effect components differently  A good rule to follow is to suspect the easy things first, if the system is dead, is it plugged in?

19. There are five main parts that handle processing: CPU, Motherboard, RAM, Hard drive, and Operating System - Here's how they are initialized:  The hard drive is a storage device, holding the operating system and programs  The CPU can't work with the software directly from the hard drive because the hard drive is too slow  The CPU needs to load the operating system into special high speed memory called random access memory (RAM) to be able to work with the OS  All software used by the computer has to load into RAM before it can be used

20. Applications and Data are stored in the Hard Drive until needed by the CPU However the Hard Drive is way too slow to deliver it to the CPU Load the application WORD Here it Comes To speed up the delivery of data to the CPU, High Speed Random Access Memory RAM is added

21. Load the application WORD Here it Comes Speed Limit 30 Speed Limit 250 High Speed RAM delivers data to the CPU

22. Once the program is in RAM, the CPU sends the update to the video card and monitor displaying the output

23. At some point in the process, especially when creating an original item, you'll want to save your changes  You can do this at the end, when you're satisfied with your work, or when you need to stop for a while and want to pick up later where you left off  Up to this point all your work is maintained in RAM which is Volatile, so if power is lost you so is your data  Saving your work copies the data back onto the hard drive which is nonvolatile

24. Save the work and call it letter to mom Call this letter to mom Copy data back from RAM onto Hard Drive

25. Nearly every modern computing device has some kind of sleep mode, a way for the device to shut almost everything down automatically.  In Windows 7, for example, go to the Start button and hover over the arrow next to Shut Down and select Sleep.  This means you don't have to turn off the computer or device every time you walk away for a few minutes