1. Introduction to Computers

2. What is computer hardware?
Hardware refers to the physical components of a computer
Chips
Circuit boards
Electronic storage
Monitors, keyboards, speakers, etc.
Any part of a computer you can touch and feel is considered hardware

3. Vital components of a computer
Vital components of a computer consist of:
Motherboard
Processor
Memory
Storage devices
Power supply
All the above are found inside the system unit
A case that holds the computer’s main components
Desktop units designed for users to open the case
Notebooks not designed for the case to be opened

4. The Motherboard A computer’s central or main circuit board
Think of it as the electronic hub of a computer
All components connect to the motherboard
Expansion slots hold additional circuit boards that provide additional functionality such as a sound card.
Connections for storage device cables
Connector for power supply
Heat sink to draw heat away from the processor. Processor is found beneath the heat sink.
2 DIMM slots for memory boards

5. The Motherboard provides
A socket for the processor
Slots to insert memory cards
Sockets to connect storage devices
Expansion slots for additional circuit boards
A connection to the power supply
Electronic pathways to link all the components

6. the Processor Executes the instructions found in a program
The largest chip on the motherboard
Can identify location of processor on motherboard by the heat sink
Heat generated by processor is a critical issue
Without a means to draw heat away from the processor, it would overheat and eventually fail
A heat sink uses metal fins to provide a large exposed surface to dissipate heat
A small fan is also often used to draw heat away

7. Memory
Temporary workspace for tasks currently being executed by the processor
Think of memory like the surface of your desk
Can do more complex tasks with more desk space
Can also handle more tasks concurrently
Extremely fast access, billionths of a second
Both programs and data stored in memory
Provided in DIMMs… a board holding a number of memory chips

8. Storage devices
Provide permanent, long-term storage for massive amounts of data
Think of a storage device like a file cabinet
Data must be retrieved from storage and placed in memory in order for a program to use it
Just like data must be moved from a file cabinet to the surface of your desk in order to work with it
Relatively slow access, thousandths of a second
Types include hard disk, DVD, micro SD, & more

9. Why both memory & storage devices?
Both serve a specific purpose
Memory is volatile
Must have power to retain data
Thus not a good option for long-term storage
Storage devices too slow for normal processing
Thousandths versus billionths of a second access
A factor of a million difference in access time
If memory access time were 1 second, storage device access time would be 275 hours.

10. Storage & memory work together
Processor needs data in tiny chunks
Memory used to hold these small chunks of data
Takes advantage of fast access speed of memory
Data in memory must come from storage
Data is retrieved from storage in massive chunks
Retrieving large amounts of data from storage at one time minimizes slow access time
Consider a Word document
Entire document retrieved from storage at one time
The document is then changed in memory

11. The Power supply Power comes from an electrical outlet, right?
So why does a computer need a power supply?
Computers operate on direct current (DC)
Electrical outlet uses alternating current (AC)
Power supply converts AC from the wall outlet to the DC needed by the computer
Power supply fails more than other components
If nothing happens when you turn the computer on, the power supply has probably died

12. Peripheral devices Most peripherals are input/output devices
Monitor Keyboard Mouse Printer
A microphone, scanner, speakers, and camera are also considered peripheral I/O devices
Most peripherals are outside the system unit