Post on 12-Jan-2016
Computer Parts
Two Basic Parts
Hardware&
Software
Computing SystemsComputers have two kinds of components:Hardware, consisting of its physical devices (CPU,
memory, bus, storage devices, ...)Software, consisting of the programs it has (Operating
system, applications, utilities, ...)
What is Hardware?Hardware is all the elements or pieces that
make up the of physical components of the computer
Consider it the physical machine.Hardware is anything that you can touch
Key Hardware ComponentsThe parts of the computer can be classified into 3 sections
CPU MemoryPeripherals & Connectors
Hardware: CPU
CPU - Central Processing UnitCPU is often called the brain of the computer
because that is where it does all the thinkingReceives program instructionsPerforms arithmetic and logical operationsControls other computer components
Consists of millions of transistors on a single microchip that plug into the motherboard
Speed of CPU is measured in Hertz – number of cycles/second
Today speed is measured in gigahertz (GHz) (billions of cycles per second
Memory
There are three main types of memory:
1. Cache Memory2. Random Access Memory (RAM)3. Persistent Storage (ROM)
Memory is where all the information is stored.
Without information the computer would be useless.
Hardware: CacheCache MemoryTemporary memory accessed by the CPUVery fast used at initial startup of computer Stores data and instructionsData is then sent to the other types of memoryStores frequently used instructions and data but quite smallTemporary – is not kept once the computer is shut down
Hardware: RAMRandom Access Memory (RAM)• Stores instructions and data• Temporary memory – not kept once the computer is
shut down• Size is dependent upon the computer• The more RAM memory the faster the computer. • It is fast, but volatile...• analogous to a person’s short-term memory.
Hardware: ROMPermanent Memory – Read Only Memory (ROM)• Stores data forever on you Hard-drive or data stick.• Older computers store information on magnetic or
optical media.PermanyStable storage using magnetic or optical media.
• Called Read Only Memory because it reads files and saves them (permanently)
• Analogous to a person’s long-term memory.• Slower to access than RAM• Cannot execute instructions
Basic Units of Memory
1 bit (0 or 1)1 byte normally consists of 8 bits
Is the storage for one character210 bytes =1024 bytes = 1 kiloByte (kB)1024 KB = 1 MegaByte (MB)1024 MB = 1 GigaByte (GB) Many people approximate in steps of 1000, not 1024
Example: a 20KB file actually has 20,480 bytes, not 20,000 bytes
Bits & BytesA bit is a 1 or a 0
They are stored in a memory address in groups of eight
8 bits = 1 byte which is the storage of one characterone byte, is the smallest unit of information that a
computer can process. 210 bytes =1024 bytes = 1 kiloByte (kB) 1024 KB = 1 MegaByte (MB) 1024 MB = 1 GigaByte (GB) Many people approximate in steps of 1000, not 1024
There are different data types for each of the many forms of data. The data type you choose will affect not only the form in which the data is stored, but also the amount of memory required to store the data.
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Hardware: Peripherals & Connectors
Peripherals: Input & Output Devices Input
Keyboard, mouse, digital pen, modem, wireless Internet connection, touch screen, joy sticks, and more
OutputMonitor, printer, speakers, modem, wireless Internet
connection, and more
Hardware: Peripherals & Connectors
Connector - The Bus:• Connects CPU to other hardware devices.• Analogous to a person’s spinal cord.• Speed measured in megahertz (like the CPU), but
typically much slower than the CPU...• The bottleneck in most of today’s PCs.
Hardware: How it WorksPutting the pieces together:
CPU
Bus
RAMMemory
ROMMemorycache
Programs are stored (long-term) in secondary memory, and loaded into main memory to run, from which the CPU retrieves and executes their statements.
What is Software?Software is information that can be stored
on the computersYou cannot touch softwareYou can only see the result of the
information on an output device like a monitor
Software is divided into two main categories
System SoftwareApplication Software
System SoftwareSystem software is the software that allows you to run the
computerIt controls and maintains the hardware. It is the interface between the hardware and the programs you
use on the computerTypes of system software:
Operating system Networking system Programming language software Web site server Data backup
Examples of system software: Linux, Windows, MacOS
Software: Operating System
Operating System (OS)The OS acts as the “manager” of the computer system,
making sure that each hardware device interacts with the others.
It enables the computer to communicate with software applications like Microsoft Word and you the user.
Examples: MacOS, Windows, Linux
Application SoftwareApplication software is all the software that allows you to work or
play on the computerIt is because of this software that we have to use computersYou will know this type of software as “program” Types of programs that are commonly used:
Word processors and spreadsheets (Word, Excel) Game programs Web browsers Photo Editors Email Graphics and Drawing
Networking and CloudsCan you imagine a world without Google?Today computers are all connected togetherA network is a collection of computers that can talk to
each otherThis world-wide collection of networks is called the
InternetThe internet makes use of two key pieces of application
software: Email and WWW
Programming LanguagesSoftware is a set of instructionsHow are instructions given to computers?
With programming languages There are three types of languages
1. Machine Languages Consists only of sequences of 0s and 1s example: 0110110111110111 0000000100000000 0000000100000000
2. Assembly Languages symbolic representation of machine language example: ADD A,B
3. High-level Languages contains English words and phrases and algebraic expressions examples of high level languages:
Python, Java, C++, VisualBasic, Fortran