Part 1 Computing Fundamentals Chapter 1 Computer Basics

Part 1, Computing Fundamentals Chapter 1, Computer Basics Lesson 1 -1, What is a computer Robert Crawford, MBA West Middle School

UNIT O BJECTIVES � Describe the four operations of a computer � Contrast analog and digital computers � Explain why data and instructions for computers are coded as 0’s and 1’s

KEY TERMS � Bit � Byte � Computer � Input � Output � Processing � Storage

Computer basics �What is a computer? ◦ try to think in general terms: �don’t just form a answer that describes a computer as it exists today �Try too think of an answer that would work both �into the past (think in terms of about 500 years). �The first use of the word “computer” was recorded in 1613 in a book called “The yong mans gleanings” �Into the future

Computer basics �What is a computer? ◦ Originally It referred to a person who carried out calculations, or computations, and the word continued with the same meaning until the middle of the 20 th century. ◦ From the end of the 19 th century the word began to take on its more familiar meaning, a machine that carries out computations.

Computer basics �What is a computer? ◦ This takes us to where we are today with this definition. . . A machine that changes information for one form into another.

Computer basics �What is a computer? ◦ A machine that changes information for one form into another. ◦ It does this by performing four basic operations.

Computer basics �What is a computer? ◦ A machine that changes information for one form into another. ◦ It does this by performing four basic operations. �Input �Processing �Output �Storage

Computer basics Analog ◦ Measures data in a scale with many values �Mercury Thermometer �Gas gauge on a car Digital � Works with data that has fixed values ◦ Typically 1 and 0 ◦ The computers you are using right now are digital computers.

Computer basics Analog Digital

Input � The raw (unaltered) information that is entered into the computer. ◦ Simple �Letters �Numbers ◦ Complex �Photographs �Videos �Music ◦ How do we get information into the computer?

Input � The raw (unaltered) information that is entered into the computer. ◦ Simple �Letters �Numbers ◦ Complex �Photographs �Videos �Music ◦ We input information into the computer using a variety of devices.

Input � Information is stored, and processed, in the computer in a very basic format. ◦ 1’s and 0’s

Input � Information is stored, and processed, in the computer in a very basic format. ◦ 1’s and 0’s ◦ A single unit of information is a Bit �Short for “Binary Digit”

Input � Information is stored, and processed, in the computer in a very basic format. ◦ 1’s and 0’s ◦ A single unit of information is a Bit �Short for “Binary Digit” ◦ These Bits are grouped together in “words” called “Bites” �For example (i. e. ) �A = 01000001 � 1 = 00110001 �This is the only way the computer sees information.

Processing � Processing is the second step in the information processing cycle.

Processing � Processing is the second step in the information processing cycle. ◦ Remember, the four operations of computers are: �Input �Processing �Output �Storage

Processing � Processing is the second step in the information processing cycle. ◦ In this step the computer manipulates (does something with) the data.

Processing � Processing is the second step in the information processing cycle. ◦ In this step the computer manipulates (does something with) the data. � This stage is largely dependent on two things: ◦ Coded Instructions ◦ Speed of processing

Processing � Processing is the second step in the information processing cycle. ◦ In this step the computer manipulates (does something with) the data. � This stage is largely dependent on two things: ◦ Coded Instructions �These are the instructions given to the computer, the program. �High Level Code (C++, Pascal, Python) �Low Level Code (machine code, assembly language) ◦ Speed of processing

Motorola MC 6800 Assembly listing, showing original assembly language and the assembled form

Processing � Processing is the second step in the information processing cycle. ◦ In this step the computer manipulates (does something with) the data. � This stage is largely dependent on two things: ◦ Coded Instructions �These are the instructions given to the computer, the program. �While this class is not a programming class, there will be more about these in future units ◦ Speed of processing

Processing � Processing is the second step in the information processing cycle. ◦ In this step the computer manipulates (does something with) the data. � This stage is largely dependent on two things: ◦ Coded Instructions ◦ Speed of processing �Speed is measured in units of cycles per second, which is called a Hertz (Hz). Computer boards and CPUs run at rates of millions and billions of Hertz, megahertz (MHz) and gigahertz (GHz). �A good speed for a PC microprocessor in 2004 was 4 GHz.

Output � The third step of the information processing cycle is output. ◦ After the computer adds two numbers the computer then presents the result; this is output. ◦ Output can take many forms.

Output � The third step of the information processing cycle is output. ◦ After the computer adds two numbers the computer then presents the result; this is output. ◦ Output can take many forms. �Image �Monitor �Sound �Speaker �Printed text �Printer �Tactile feedback �PS 4 vibrating controller

Storage � The four the operation is storage.

Storage � The four the operation is storage. ◦ What would happen without computer storage?

Storage � The four the operation is storage. ◦ Without computer storage all of the work you do on the computer would be lost. ◦ By storing the data you can access it and use that data at a late date. �We will talk more about storage in the next, and other future, units.

Things to remember

Things to remember � Work with the person next to you and try to think of things that you should expect to see on an examination.

Activity � Use a sequence chart to place the four operations of computers in their correct order