week 1 to 3

Pervasive computing

Also known as ubiquitous computing

Computers have become an integral part of our lives

Basic computer literacy

Knowing about and understanding computers and their uses is an essential skill today for everyone

Before 1980

Computers were large, expensive

Very few people had access to them

Computers were mostly used for high-volume processing tasks

Microcomputers in the early 80s

Inexpensive personal computers

Computer use increased dramatically

Reference and Communication

Productivity

Enterntainment

Computers at Home

Computer Labs and Classrooms

Campus Wireless Hotspots

Distance Learning

Computers in Education

Offsite Communications

Authentication

Computer on the Job

M-Commerce Systems

Consumer Authentication Ssystems

Portable Computers

econsumer kiosking

Computers on the Go

Input - Process - Output - Storage

Computer Basic Operation

Programmers

Systems analysts

Computer operations personnel

Security specialists

Computer Users and Professionals

Computer professionals include:

Embedded computers

Mobile devices

Personal computers

Midrange servers

Mainframe computers

Supercomputers

Categories of Computers

The computer-oriented society also has risks

• Computer viruses and malware

• Identity theft and phishing

• Privacy issues

Less formal than traditional

Netiquette

Emoticons

Differences in online communications

Check your source, not all information on the Internet is accurate.

The anonymity factor

Information Integrity

Bit

The smallest unit of data that a binary computer can recognize (a single 1 or 0)

= 8 bits

terminology used to express the size of documents and other files, programs, etc.

Prefixes are often used to express larger quantities of bytes: kilobyte (KB), megabyte (MB), gigabyte (GB), terabyte (TB), etc.

Byte

Numbering system

A way of representing numbers

Decimal numbering system

Uses 10 symbols (0-9)

Uses only two symbols (1 and 0) to represent all possible numbers

Binary numbering system

ASCII (American Standard Code for Information Interchange

: coding system traditionally used with personal computers.

EBCDIC (Extended Binary-Coded Decimal Interchange Code

developed by IBM, primarily for mainframe use

Unicode

newer code (32 bits per character is common); universal coding standard designed to represent text-based data written in any ancient or modern language

Replacing ASCII as the primary text-coding system

Graphics

(still images such as photos or drawings)

Bitmapped images

A variety of bit depths are possible (4, 8, 24 bits)

More bits = more colors

Audio data

Must be in digital form in order to be stored on or processed by a computer Often compressed when sent over the Internet Amount of data can be substantial but can be compressed

Video data

Displayed using a collection of frames, each frame contains a still image

Machine Language

Binary-based language for representing computer programs the computer can execute directly

System unit

The main housing of a computer

Houses the processing hardware for a computer

Also contains storage devices, the power supply, and cooling fans

Houses the CPU, memory, interfaces to connect to peripheral devices (printers, etc), and other components such as CD/DVD drives

With a desktop computer, usually looks like a rectangular box

Central Processing Unit (CPU)

circuitry and components packaged together and connected directly to the motherboard

Does the vast majority of processing for a computer

Also called a processor; called a microprocessor when talking about personal computer

• Typically different CPUs for desktop computers, portable computers, servers, mobile devices, consumer devices, etc.

• Often made by Intel or AMD

Dual-core CPU

Contains the processing components (cores) of two separate processors on a single CPU

Quad-core CPU

Contains 4 cores

CPU clock speed

One measurement of processing speed

Measured in megahertz (MHz) or gigahertz (GHz)

Higher CPU clock speed = more instructions processed per second

An alternate measure of processing speed is the number of instructions a CPU can process per second. Megaflops, gigaflops, teraflops

Other factors (CPU architecture, memory, bus speed, amount of RAM, etc.) also affect the overall processing speed of a computer

Benchmark tests

: Can be used to evaluate overall processing speed

Bus

An electronic path over which data can travel

Bus width

The number of wires in the bus over which data can travel

Bus width and speed determine the throughput (or bandwidth) of the bus

Arithmetic/Logic Unit (ALU):

Performs integer arithmetic and logical operations

Floating Point Unit (FPU)

Performs decimal arithmetic

Control unit:

Coordinates and controls activities

Pre-fetch unit

Tries to fetch data and instructions before they are needed from cache or RAM

Decode unit

Translates instructions so they are understood by the control unit, ALU, and FPU

Internal cache and registers

Store data and instructions needed by the CPU

Bus interface unit

Allows the core to communicate with other CPU components

System clock:

Timing mechanism within the computer system that synchronizes the computer’s operations

Machine cycle

The series of operations involved in the execution of a single machine level instruction

Memory

refers to chip-based storage

RAM (random access memory)

Computer’s main memory

Registers

High-speed memory built into the CPU; used by the CPU

ROM (read-only memory):

Non-volatile chips located on the motherboard into which data or programs have been permanently stored

Retrieved by the computer when needed

Being replaced with flash memory for firmware

Flash memory

Type of nonvolatile memory that can be erased and reprogrammed

Heat

A continuing problem for CPU and computer manufacturers

Fans

Used on most personal computers

Heat sinks

Small components typically made out of aluminum with fins that help to dissipate heat

Water cooling systems

Cool the computer with liquid-filled tubes

Notebook cooling stands

These stands cool the underside of a notebook computer by allowing better air circukation.

Expansion slot

A location on the motherboard into which expansion cards are inserted

Expansion card

A circuit board used to add additional functionality or to attach a peripheral device

ExpressCard modules:

Designed for

notebook computer

expansion

Bus

An electronic path within a computer over which data travels

Expansion bus

Connects the CPU to peripheral (typically input and output) devices

Memory bus

connects CPU directly to RAM

Frontside bus:

connects CPU to I/O bridge

Port

A connector on the exterior of a computer’s system unit to which a device may be attached

Nanotechnology

The science of creating tiny computers and components less than 100 nanometers in size

Quantum computing

Applies the principles of quantum physics and quantum mechanics to computers

Cases

Influences the motherboard form factor choice

Must allow for good airflow

Available in different sizes

Power Supplies

Provides power to all computer components.

Must be chosen based on current and future needs.

Deliver different voltage levels to meet different internal component needs.

Motherboards

The backbone of the computer

Interconnects computer components

CPU

The brain of the computer

Most processing is done by the

Cooling Systems

Dissipates the heat generated by computer components.

RAM

Stores data temporarily, aiding processing

ROM

Stores data permanently; often storing firmware and low-level programs.

Adapter Cards and Expansion Slots

extend computer functionality

connect to the motherboard through Expansion Slots

Storage Devices

• Adapter Cards extend computer functionality

• Adapter Cards connect to the motherboard through Expansion Slots

Video Ports

Connects a video system to an external display device such as a monitor or projector

Video systems are often designed as an adapter card.

General Ports

Provide connectivity between the motherboard and various external devices such as printers, external storage, and video cameras.

Video Ports and Related Cables

A few different standards govern video traffic between the computer and external video devices.

HDMI and Display Port are examples of video ports that require a specific cable to operate.

Other Ports and Related Cables

Motherboards have a number of other ports used for device connectivity; USB is a common example.

Adapters and Converters

can be a solution if a motherboard does not have the proper port to connect to a device.

Adapters

do not usually process the signal; they simply redirect it to another pin.

Converters

are more likely to process and transform the signal, converting it to be accepted by an existing port.

Thin clients

have little processing power and are designed to act as a terminal to a server (thick client).

Thick clients

have more powerful CPUs, more memory, and their own storage. They serve as processing stations for thin clients.

CAx Workstations

Designed to support CAD and CAM applications.

Plenty of RAM, fast disks, powerful CPU, and special input devices are common resources.

Audio and Video Editing Workstations

Common editing workstation resources include much RAM, fast disks, powerful CPU and special adapter cards such as audio and video capture

Virtualization Workstations

These workstations are designed to run virtual computers

Virtual computers use and share the workstation’s physical resources such as CPU, memory, and disks.

The selection of physical resources will depend on the number and purpose of virtual machines.

Gaming PCs

Due to the high resource requirements of modern games, gaming PCs are very resource-demanding.

A few requirements of gaming PCs are top-end CPU, lots of fast RAM, fast disks, high-performance input devices, and audio systems.

Home Theatre PCs

These computers must be able to play various media formats and, in some cases, receive TV signals.

Common HTPC requirements include powerful CPU, fast RAM, large disks, fast NIC, and video cards with the TV input.