Computer Savvy

What is a Computer Inside the PC Software Networks

What is a Computer History Components of a Computer System Operating System Bits and Bytes

History IBM announced its version of the personal computer (PC) in 1981 and broke a longstanding corporate tradition by going to external sources for supporting hardware and software. Intel designed the microprocessor. Microsoft developed the operation system. Today, PC is a generic term for any computer that is based on Intel-compatible hardware and that runs Microsoft. Charles Babbage (1792-1871) went broke trying to build a general purpose computing device he called the Analytical Engine. Babbage’s machine would have been the world’s first computer.

A is an electronic device that accepts data (input), then manipulates or processes that data to produce information (output). It operates under the control of a (or set of instructions) that is stored internally within the computer’s memory. computer program

What is an Operating System? Every computer functions the same way. The CPU accepts data from an input device or auxiliary storage, stores it temporarily in memory while it computes an answer, then sends the result to an output device or auxiliary storage. All of this happens under the control of an operating system, a computer program (actually many programs) that links the various components of a computer to one another.

Central processing unit Memory Central processing unit (CPU) Output Input Disk Disk Auxiliary storage

The central processing unit (CPU) is the “brain” of the computer and performs the actual calculations.

Memory (which is also known as random access memory or RAM) temporarily stores any program being executed by the computer, as well as the data on which the program operates.

Auxiliary storage (also called secondary storage or external storage) provides a place where data can be permanently stored, and then transferred to and from main memory. A floppy disk, hard disk, CD-ROM, DVD, high-capacity removable media, and tape backup unit are the primary types of auxiliary storage used with a PC.

Input devices accept data from an external source and convert it to electric signals, which are sent to the CPU. Virtually every PC is configured with a keyboard and mouse as its input devices. A joystick, scanner and microphone are other common input devices. Auxiliary storage is also considered an input device.

Output devices accept electric signals from the CPU and convert them to a form suitable for output. The monitor and printer are common output devices. Speakers are also considered and output device and are necessary in order to hear sound from a PC. Auxiliary storage is also considered an output device.

Bits and Bytes Computer memory and storage capacity is described in bytes. Each byte holds 8 bits or 1 ASCII character. A kilobyte, megabyte, and gigabyte are approximately one thousand, one million, and one billion bytes, respectively.

American Standard Code for Information Interchange (ASCII) The ASCII for short and pronounced “as key” can be either a 0 or 1. Since there are 8 bits in each byte and there are 2^8 (or 256) possible combinations of 0’s and 1’s that can be stored in a byte.

Can you use the ASCII codes for the uppercase letters to figure out the message? 01001000 01000101 01001100 01001100 Check Your Answer 01001111

01001000 01000101 01001100 01001100 01001111 H E L L O “hello” in ASCII

Your Understanding How many bits are in a byte? 24 8 16

Try again Each byte holds 8 bits or 1 ASCII character

Yes Each byte holds 8 bits or 1 ASCII character

Your Understanding 2. The size of a computer’s memory refers to: The capacity of its hard disk The amount of ROM available. The amount of RAM available.

Try again Memory is also known as random access memory or RAM

Yes Memory is also known as random access memory or RAM

Central processing unit Your Understanding 3. Fill in the missing parts: a. 1. input 2. memory b. 1. disk 2. output c. 1. input Memory Central processing unit (CPU) 2. 1. Disk Disk Auxiliary storage

Good try Every computer functions the same way. The CPU accepts data from an input device or auxiliary storage, stores it temporarily in memory while it computes an answer, then sends the result to an output device or auxiliary storage. All of this happens under the control of an operating system, a computer program (actually many programs) that links the various components of a computer to one another.

Wow Every computer functions the same way. The CPU accepts data from an input device or auxiliary storage, stores it temporarily in memory while it computes an answer, then sends the result to an output device or auxiliary storage. All of this happens under the control of an operating system, a computer program (actually many programs) that links the various components of a computer to one another

Inside the PC History Microprocessor Memory Storage Input Monitor Printer

Did you know? IBM announced its version of the personal computer (PC) in 1981 and broke a longstanding corporate tradition by going to external sources for supporting hardware and software. Intel designed the microprocessor. Microsoft developed the operating system. Today, PC is a generic term for any computer that is based on Intel-compatible hardware and that runs Microsoft software.

Computer Station

Rear of the Computer

Inside the Computer

The Microprocessor The brain of the PC. The fundamental unit of the microprocessor is the transistor- the on/ off, zero/one switch that is at the heart of the digital computer. The key to improving the performance of a microprocessor is to increase the number of transistors; the more powerful the microprocessor.

A microprocessor is a single silicon chip containing the PC’s CPU A microprocessor is a single silicon chip containing the PC’s CPU. An example is Intel’s Pentium IV, a well know name of a microprocessor.

Moore’s Law In 1965 Gordon Moore, the founder of Intel, predicted that transistor densities would continue to double every 18 months, a prediction that has held, and that accounts for the incredible increase in computer power.

Memory The microprocessor is the brain of the PC, but it needs instructions that tell it what to do, data on which to work, and a place to store the results. All this takes place in the memory. The memory of a computer (also known as random access memory or RAM) is divided into individual storage locations, each of which holds one byte.

Memory 10001101 10000001 11110000 10101010 11100001 10000101 11100101 10010101 11000001 11100011 10001100 11001101 11110001 A computer’s memory can be thought of as a large grid, with each cell corresponding to a single memory location, capable of holding a single ASCII character.

auxiliary storage devices a floppy drive a hard (fixed) disk CD-ROM DVD zip drive removable memory stick

How Disk Storage Works Computer disks – both floppy and hard – are flat dishes coated on both sides with a magnetic film. When a disk is formatted, magnetic codes are embedded in the film to divide the surface of the disk into sectors (pie slice wedges) and tracks (concentric circles). They organize the disk so that the data can be recorded in a logical manner and accessed quickly be the read/write heads that move back and forth over the disk as it spins.

Back up Your Data! I urge you to take time at the end of every session to back you the files you cannot afford to lose. You need not copy every file, only the data files that were changed during that session. It takes only a few minutes, but one day you will thank me! Save!

What is Drive C? The CPU needs to differentiate one auxiliary storage device from another and does so by designating each device with a a letter. Floppy is Drive A Hard disk is Drive C Others Drive D and on

The keyboard and mouse are the primary input devices for the PC The keyboard and mouse are the primary input devices for the PC. The standard mouse has two buttons and recognizes four basic operations: Point Click Double click Drag

The Mouse or the Keyboard Almost every command can be executed in different ways, using either the mouse or the keyboard. Most people start with the mouse and add keyboard shortcuts. There is no right or wrong, just different techniques, and the one you choose depends entirely on your personal preference.

A monitor is an output device A monitor is an output device. It’s resolution is defined as the number of pixels (picture elements) that are displayed at one time

Resolution and Monitor Size Higher resolutions require larger monitors Monitor is measured by its dot pitch; the smaller the dot pitch the crisper the image 800 x 600 displays 24 rows and 10 columns 1024 x 768 has 34 rows and 13 columns

Printer A printer produces output on paper. The output is referred to as hard copy because it is more tangible than files written to a disk. Printers vary greatly in design price and capability.

Typefaces and Point Sizes This is Times New Roman 10 point This is Times New Roman 12 point This is Times New Roman 18 point This is Times New Roman 24 point This is Times New Roman 32 point This is Arial 10 point This is Arial 12 point This is Arial 18 point This is Arial 24 point This is Arial 32 point

Your Understanding 1. The brain of the PC is: microprocessor memory monitor

I don't think so The microprocessor is the brain of the PC

The microprocessor is the brain of the PC Your Good

Your Understanding 2. ______ is a/an auxiliary storage device. floppy CD Memory stick All the above

mistake

good for you

Your Understanding 3. Hard copy refers to: The difficulty of duplicating disk Printed material Written material that is difficult to read

A printer produces output on paper A printer produces output on paper. The output is referred to as hard copy because it is more tangible than files written to a disk. try again

A printer produces output on paper A printer produces output on paper. The output is referred to as hard copy because it is more tangible than files written to a disk. Great!

Software History System software Application software Antivirus software

history The operating system determines the types of applications the system can run. Windows 95 was the first of the “modern” systems. Windows 98 and its successor, Windows Me, are intended for the home user. Windows NT and Windows 2000 are aimed at business. All four have the same interface as Windows 95. The most powerful computer system is useless without appropriate software. It is divided into two classes- system (referred to as the operating system) and application software.

System Software The system software (consisting of the operating system and supporting programs) is a program (actually many programs) that links the hardware components to one another. It is this system that lets you enter text at a keyboard, have it displayed on a monitor, stored permanently on disk, then appear on the printer.

An application program (Microsoft Word) forwards your commands to the operating system, which does its work behind the scene. The wonderful thing about Application Software Is that replacing an application with another completely changes the personality of the computer.

Garbage In, Garbage Out (GIGO) A computer does exactly what you tell it to do, not always what you want it to do. No system, no matter how sophisticated, can produce valid output from invalid input. In other words, garbage in – garbage out.

Microsoft Office XP contains four major applications Word word processing Excel spreadsheets Access database PowerPoint presentations

Microsoft Word

Microsoft Excel

Microsoft Access

Microsoft PowerPoint

Antivirus Software A computer virus is an actively infectious program that alters and/or erases the files on your system. Your computer is at risk to virus attack every time it reads a floppy drive, receives an e-mail, or downloads a file from the Internet. Antivirus software and continual updates is essential.

Your Understanding __________ is a program that links the hardware components to one another. Antivirus software Application software System software

System software is a program that links the hardware components to one another. nope

System software is a program that links the hardware components to one another. Great!

Your Understanding 2. ________ such as Microsoft Word, forwards your commands to the operating system, which does its work behind the scene. Antivirus software Application software System software

try again Application program (Microsoft Word) forwards your commands to the operating system, which does its work behind the scene.

An application program (Microsoft Word) forwards your commands to the operating system, which does its work behind the scene. Good!

Your Understanding 3. Your computer is at risk to virus attack every time it reads: a floppy drive receives an e-mail downloads a file from the Internet All of the above

Your computer is at risk to virus attack every time it reads a floppy drive, receives an e-mail, or downloads a file from the Internet. try again

Your computer is at risk to virus attack every time it reads a floppy drive, receives an e-mail, or downloads a file from the Internet. Right

Networks WAN LAN Internet

A network is a combination of. hardware and software that. lets A network is a combination of hardware and software that lets connected computers share resources and communicate with each other. The computers may be across the country or around the world, or it may be limited to the computers on the same floor of a building.

A network may be a wide area network or WAN that encompasses computers across the country or around the world.

Your school computers are connected to a local area network. A network may be a local area network or LAN when the connected computers are limited to the computers on one floor of a building. Your school computers are connected to a local area network.

Almost all computer break-ins occur because of a poorly chosen password. A 4 letter password has fewer than 500,000 combinations- it can be hacked in 30 seconds 8 letters has 200 billion! 8 letters and numbers combination has 2 trillion!!! Protect Your Password!

Internet The is a network of networks. The World Wide Web is a very large subset of the Internet, consisting of those computers that store hypertext and hypermedia documents.

What do I need for the Internet? A browser like Internet Explorer or Netscape Navigator is required to view documents from the Web. A connection to the Internet is made through a LAN or by connection to an Internet Service Provider (ISP) like a modem, cable modem, or DSL line.

Electronic mail E-mail is the most widely used Internet service. An e-mail address follows the general format username@mailserver. All e-mail systems provide the same basic commands t compose, send, reply, and forward email.

Your Understanding 1. A network may be a ____ when the connected computers are limited to the computers on one floor of a building. WAN LAN WEB

A network may be a local area network or LAN when the connected computers are limited to the computers on one floor of a building. try again

A network may be a local area network or LAN when the connected computers are limited to the computers on one floor of a building. Great!

Your Understanding 2. A network may be a ____ that encompasses computers across the country or around the world. WAN LAN WEB

Try again A network may be a wide area network or WAN that encompasses computers across the country or around the world.

Yes A network may be a wide area network or WAN that encompasses computers across the country or around the world.

The End