AN INTRODUCTION TO THE COMPUTER

Transcription

1 AN INTRODUCTION TO THE COMPUTER

2 COMPUTER a machine that follows instructions to accomplish a task

3 HARDWARE Any physical components of a computer SOFTWARE Any instructions followed by the computer

4 CATEGORIES OF HARDWARE 1.Processor (CPU) 2.Memory (Primary Storage) 3.Secondary Storage 4.Input & Output (Human/Computer Interaction) 5.Communications (with other computers and devices)

5 CATEGORIES OF HARDWARE PROCESSOR (CPU) - Controls all other hardware components - Executes (follows) simple instructions - Arithmetic: + - X (sometimes more: sin() cos()) - Relational: < > = - Logical: and or not - Move (Copy) very small units of data/instructions - Holds only a few small units of data/instructions

6 CATEGORIES OF HARDWARE MEMORY (Primary Storage) - Short Term / Temporary storage of data and instructions currently in use. - Organization: set of Locations, where each Location: - stores one instruction or a small unit of data (Contents) - has a numeric Address - Data/instructions must be in memory for the CPU to use it - Volatile: contents lost when power is lost

7 CATEGORIES OF HARDWARE SECONDARY STORAGE -Long term storage of data and instructions -Organization: similar to Memory (Locations) -Non-Volatile: information saved without power -Larger than Memory (more Locations) -Slower access by CPU (must be copied to Memory) -Ex: Hard Drive, Thumb Drive, DVD, CD, Tape

8 CATEGORIES OF HARDWARE INPUT & OUTPUT -Allows the computer to interact with a human -Input: allows the human to enter information into the computer (ex: mouse, keyboard, microphone, scanner, camera). -Output: allows the computer to deliver information to a human (ex: monitor, speaker, printer)

9 CATEGORIES OF HARDWARE COMMUNICATIONS -Allows the computer to send/receive data to/from other computers and devices. -May be wired (NIC: Network Interface Card, modem) or wireless (Bluetooth, cellular)

10 BASIC DIAGRAM OF A COMPUTER

11 DIGITAL INFORMATION ALL data and instructions are stored in terms of two digits: 1 & 0 Why? For the engineers: -an on/off switch is the simplest machine component. -a machine that constantly transforms itself is most easily built from the simplest components.

12 DIGITAL INFORMATION Physical Representation Volatile hardware: electricity is On or Off Non-Volatile hardware: depends on the physical medium. Ex: -Hard drive: magnetic (attract or repel) -DVD: laser reflection (reflects or does not reflect)

13 UNITS OF MEASURE Processor Cycle: a single action of a CPU -Fetch: copy an instruction from memory -Execute: follow/carry out an instruction Hertz: cycles per second Kilohertz: 1,000 cycles per second Megahertz: 1,000 kilohertz

14 UNITS OF MEASURE Storage Bit a single digit (1 or 0) Byte 8 bits Kilobyte 1,024 bytes Megabyte 1,024 kilobytes Gigabyte 1,024 megabytes

15 UNITS OF MEASURE Storage Word the size of a memory location -unit of data used by most computer operations -size varies by computer model (1,2,4,8,etc. bytes) - Ex: in a 64-bit machine, a Word is 8 bytes.

16 CATEGORIES OF SOFTWARE Application Performs a particular task (Ex: mail, game, word processor, internet browser) Application Support Utilities used by multiple applications (Ex: MS.Net, Java Runtime Environment) Systems Operating System: Control of Hardware, User Interface & App Services (Ex: MacOS, MS-Windows, Linux)

17 VOCABULARY SUMMARY Term Computer Hardware Software Processor Memory Location Volatile: Secondary Storage Input/Output Communications Hertz Definition A machine that follows instructions to accomplish a task Any physical components of a computer. Any instructions followed by the computer. Computer hardware category that controls all other hardware and follows (executes) the instructions. Short term/temporary storage of data and instructions currently in use. An individual element of memory, it stores one instruction or one small piece of information. It has an Address and Contents. Describes hardware where information is lost when electricity is lost. Long term, non-volatile storage if information. It is larger but slower for the CPU to access information stored here as compared to Memory. Ex: hard drive, thumb drive, DVD. Category of hardware that allows the computer to interact with a human. Ex: Keyboard, Mouse, Monitor, Speaker. Category of hardware that allows the computer to share information with other computers and devices. A unit of measure of the processor, meaning 1 cycle per second.

18 VOCABULARY SUMMARY Term Definition Kilohertz Megahertz 1,000 hertz 1,000 kilohertz Bit A single binary digit (1 or 1) Byte Kilobyte Megabyte Gigabyte Word Application Application Support Operating System 8 bits 1,024 bytes 1,024 kilobytes 1,024 megabytes The size of a memory location expressed in bytes. The exact number varies by CPU model. Software that performs a particular task. (Ex: , game, word processor) Software consisting of utilities shared by multiple applications (Ex: MS.Net, Java JRE). Software that controls the hardware, provides an interface for the user to command the computer to perform tasks, and provides services for applications.